Nereididae is among the most familiar of marine annelid families, common and well-studied in most marine environments but paradoxically no recent key or identification guide exists to the world’s genera. Here updated generic descriptions, a list of characters, a linear key to genera, and minimal diagnoses that distinguish each genus from all others in the family are provided. This information is generated from a Delta database of 186 morphological characters and a link is provided to downloadable software allowing the same data to be interrogated using the open-source Delta program Intkey – a nonlinear multiple entry point computerised interactive key. For each genus the recent literature is also summarised, comments on taxonomic status provided, and published keys to species cited. Nexus format matrices are provided for all 45 genera and 158 Nereididae species, representing all genera, scored for 146 multistate characters from the same character list to facilitate future phylogenetic studies. Nereididae is probably the best-known of all the families of marine annelids (“polychaetes”) – the family includes many species that are commonly encountered world-wide, intertidally, and also in diverse habitats from ephemeral freshwaters to abyssal depths . Nereididae are almost invariably used as exemplars of marine Annelida in invertebrate zoology textbooks  and a downloadable interactive identification tool (= Taxonomic Information System) using the Delta Intkey software ;to discriminate all genera based on minimal diagnoses (see Systematic account of genera);to provide a character list (see Nereididae characters) and Nexus format data matrices  for inclNereididae taxa (CSIRO)is still available as Windows only software via We used the Delta (Descriptive Language for Taxonomy) suite of programs to create and manage taxonomic data to support objective and quantitative description and discrimination of dae taxa . The oriNereididae genera), linear keys (see below and Key to genera of Nereididae), interactive keys and Nexus files .Delta comprises several separate applications: the Delta Editor manages taxon by character data and generates outputs via scripts . For the purposes of this paper, principal outputs are natural language descriptions and diagnoses of taxa .We concur with RBASE = 2.00 ABASE = 1.00 REUSE = 1.01 VARYWT = 0.80; Number of confirmatory characters = 2. Following the recommendation of RBASE), evenness of subdivisions based on abundance indices, , minimising re-use of characters (REUSE) and treatment of variable characters (VARYWT); The key was generated by the Delta Confor program with the following settings: Characters and character states are described and illustrated in the following section. The downloadable Intkey interactive key associated with this paper includes a more comprehensive set of character state illustrations. Two Nexus files are provided as Suppl. materials Nereididae are available as a separate download  andMuseum Victoria (NMV),or derived from the literature as credited in the figure captions. Some characters are included even though their potential to inform higher level relationships are not yet tested, for example: palpophore surface (character 4), and prostomium longitudinal groove (character 9). We have also included some characters useful for distinguishing species . Meristic characters, in particular paragnath counts, are thus far rarely used to characterise nereidid genera – typically such characters require data from large numbers of specimens if they are to be the basis of robust taxonomic conclusions  and Unanereiszghali). Nereididae specimens, in which case both species of Unanereis may be referable to Ceratonereis or Solomononereis.All 2. Palps [NEXUS: palp orientation]anteriorly directed.ventrally directed.Nereisagulhana. However, in some taxa, e.g., Micronereis and some Kainonereis and Platynereis species, the palps are distinctly ventrally directed and not fully visible in dorsal view. Examples of ventrally directed palps are Micronereisbansei, Kainonereisalata and Platynereisaustralis. Caution is required utilising this character alone for identification since, at least in Kainonereis and Platynereis, this condition seems to be expressed in epitokes and not always confirmed for atokes. Furthermore, it is plausible that palps which may have been ventrally directed in live epitokes may be distorted into an anteriorly directed palps orientation as an artefact caused by preservation with pharynx extended  sub-ovoid , obtusely conical , and subconical  ). The present 2-state system is an attempt to describe more effectively the variation in the family. Thus, barrel-shaped palpophores (most genera) have an approximately equal width from base to palpostyle. They are not overly large compared to the size of the palpostyle, and in some cases may be of similar length and usually they have a transverse groove  , b. Howeove Fig. . Variabi4. Palpophore surface [NEXUS: palpophore surface]without grooves or striae .Nereididae except members of the genus Micronereis which have an undivided roughly spherical palp that is also ventrally located on the anterior prostomium; see Micronereisbansei).A biarticulate palp with a distinct distal palpostyle is present in all 6. Palpostyles for m [NEXUS: palpostyles form]spherical.subconical.acutely conical.Micronereis) are recognised as having three shapes: spherical, subconical , and acutely conical. The palpostyles are spherical in members of the Namanereidinae, as illustrated by Namalycastisabiuma). Some members of the genera Ceratocephale and Gymnonereis have palpostyles that are acutely conical e.g., Ceratocephaleaureola), Gymnonereisminyami), Perinereiscaeruleis). This character is also useful for species separation across several unrelated genera of Nereididae.Palpostyles  and Neanthesbioculata).Two pairs of eyes are present in most 8. Prostomium anterior margin [NEXUS: prostomium anterior margin]entire Fig. .indented , Namalycastisborealis) and Ceratonereis spp.).The prostomium in 9. Prostomium longitudinal groove [NEXUS: prostomium longitudinal groove]present  distinguishes Namalycastis and Namanereis from most other nereidids.Terminology for characters 10 and 11 follows 11. Tentacular belt [NEXUS: tentacular belt divided]fused, separate segments not recognisable.represented by two distinct segments each carrying a pair of tentacular cirri.12. Tentacular cirri comprising [NEXUS: tentacular cirri number]four pairs.three pairs.13. Tentacular cirrophores [NEXUS: tentacular cirrophores]1. present.2. absent (cirri undivided).14. Tentacular cirri extending to chaetiger (number)Ceratonereis spp. and Platynereis spp.). Generally the posterodorsal pair is the longest.Small variations in the length of these cirri on the tentacular belt is often not a useful statistic, but may assist in recognising taxa which have very long tentacular cirri  are a pair of organs that are prominent and easily visible if present, but only by dissection. The oesophageal caeca are located immediately posterior to the muscular pharynx. at the start of the oesophagus. Their utility in taxonomy was first suggested by 18. Jaws [NEXUS: jaw dentition]with smooth or slightly crenulate cutting edge Fig. .with dentate cutting edge Fig. .Neanthes spp., Perinereis spp.), while others have finer, translucent jaws . However, many taxa are intermediate between these conditions, and abrasion may falsely result in the appearance of “smooth” jaws. Differences in the chemical composition of nereidid jaws may offer the best opportunity to distinguish taxa, but these studies have yet to be undertaken systematically.Variation in jaw morphology is as yet not well understood. Some taxa have jaws with smooth or faintly crenulate cutting edge, while others have distinctly or indistinctly toothed jaws. In some taxa the jaws are robust and dark  and Neanthescapensis).These are the smooth bar paragnaths of Thus, bar-like paragnaths are distinct from “melted paragnaths” described and illustrated by 42. Area IV smooth bar-like paragnaths: numberNeanthes and Perinereis, in addition to cones a separate patch of bar-shaped paragnaths occurs at the maxillary end of Area IV; these bars are counted separately.Paragnaths on Area IV are typically roughly conical in shape, though variations range from flattened domes of irregular shape to tooth-like paragnaths. In some taxa, particularly species of 43. Area IV rod-like paragnaths [NEXUS: Area IV rodlike paragnaths]present.absent.44. Area IV rod-like paragnaths: number45. Oral ring papillae [NEXUS: oral ring papillae]present.absent.46. Oral ring papillae: number47. Oral ring papillae arrangement [NEXUS: oral ring papillae arrangement]solitary.arranged in tufts.48. Area V papillae [NEXUS: Area V papillae]present.absent.49. Area V papillae: numberCeratocephale spp., Area V and VI contain up to three papillae in total; these are here interpreted as all occurring in Area V, with VI = 0,0.In 50. Area VI papillae [NEXUS: Area VI papillae]present.absent.51. Area VI papillae: number52. Areas VII-VIII papillae [NEXUS: Areas VIIVIII papillae]present.absent.53. Areas VII-VIII papillae: number54. Areas VII-VIII papillae arranged [NEXUS: Areas VIIVIII papillae rows]in a single row.in a double row.nd (posterior) row may be hard to see unless the pharynx is completely everted.Where a double row of papillae is present, the 255. Oral ring paragnaths [NEXUS: oral ring paragnaths]present.absent.56. Oral ring paragnaths (discrete or continuous) [NEXUS: oral ring paragnaths arranged]with Areas V, VI and VII-VIII discrete.comprising a continuous ring dorsally and ventrally, discrete groups not recognisable.57. Oral ring paragnaths on Areas V and VI (discrete or continuous) [NEXUS: Areas VVI paragnaths]form discrete groups.continuous, not recognisably distinct.58. Oral ring pyramidal paragnaths Fig.  [NEXUS: present.absent.Pyramidal paragnaths have a quadrangular base and taper to a pointed apex : 309.59. Crown-shaped oral ring paragnaths Fig.  [NEXUS: present.absent.60. Crown-shaped oral ring paragnaths: number61. Area V conical paragnaths [NEXUS: Area V conical paragnaths]present.absent.62. Area V conical paragnaths: number63. Area V conical paragnaths arranged [NEXUS: Area V cones arranged]in a triangle.in a longitudinal line.irregularly.64. Area VI paragnaths [NEXUS: Area VI paragnaths]present.absent.65. Area VI paragnaths arranged [NEXUS: Area VI paragnaths arranged]in a roughly circular group.in lines or arcs.Neanthes, an alternative arrangement of cones occurs: a distinct line or arc.Area VI paragnaths are usually arranged in a circular or irregular compact group (sometimes of only one or two paragnaths). In some species of 66. Area VI conical paragnaths [NEXUS: Area VI conical paragnaths]present.absent.67. Area VI conical paragnaths: number68. Area VI smooth bars Fig.  1. present.2. absent.73. Area VI rod-shaped paragnaths: number of rows74. Areas VII-VIII paragnaths [NEXUS: Areas VIIVIII paragnaths]present.absent.75. Areas VII-VIII conical paragnaths [NEXUS: Areas VIIVIII cone paragnaths]present.absent.76. Areas VII-VIII conical paragnaths: numberAreas VII-VIII typically forms a continuous ventro-lateral band of paragnaths and is recorded as such. In a few taxa the Areas VII-VIII band of paragnaths is extended through the dorsal region and encircles the oral ring of the pharynx; in this case even though the band nominally extends through the dorsal Areas V and VI, they are indistinguishable and the count is recorded for Areas VII-VIII.77. Areas VII-VIII conical paragnaths arranged [NEXUS: Areas VIIVIII cones arranged]in isolated patches.in one or more irregular lines forming a continuous band.Cheilonereisperistomialis Benham, 1916, the paragnaths on Areas VII-VIII are arranged in distinct isolated patches. In other nereidids the arrangement is an irregular but continuous band made up one or more rows deep.In a few nereidid species, e.g., 78. Areas VII-VIII conical paragnaths (size distribution) [NEXUS: Areas VIIVIII cones sizes]similar in size, or irregular mix of large and small paragnaths in a single band.differentiated, with a separate band of minute paragnaths also present.Typically the paragnaths on Areas VII-VIII comprise a variety of sizes irregularly arranged. However, in some taxa there is differentiation into an anterior band of paragnaths similar in size to elsewhere on the proboscis, and a separate band of minute paragnaths.79. Areas VII-VIII P-bar paragnaths Fig.  [NEXUS: present.absent.80. Areas VII-VIII P-bar paragnaths (interspersed/discrete) [NEXUS: Areas VIIVIII Pbar arrangement]interspersed with conical paragnaths.forming a separate band.81. Areas VII-VIII rod-shaped paragnaths Fig.  present.absent.Ceratocephaleloveni) and by Ceratocephaleandaman) that presence/absence of mid-dorsal papilla is variable and likely to be related to size or sexual maturity. However, the description of Ceratocephalepapillata de León-González & Góngora-Garza, 1992 is based on 155 specimens, all of which have mid-dorsal papilla. In other species of Ceratocephale, observations on mid-dorsal papillae should be interpreted with caution.It has been shown by 87. Transverse dorsal lamellae mid-dorsal papilla commencing chaetiger88. Notopodium [NEXUS: notopodium development]with at least one distinct ligule or lobe.strongly reduced, without distinct lobes or ligules.According to nautical wisdom, boats are defined as vessels able to be carried on ships. Parapodial lobes and ligules are distinguished according to a similar logic: lobes can be carried on ligules, but not vice versa. In general, ligules are larger and flatter than the smaller, conical lobes.89. Dorsal notopodial ligule Fig.  chaetiger 1.chaetiger 3.chaetiger 4.chaetiger 5.91. Dorsal notopodial ligule, length on anterior chaetigers [NEXUS: dorsal notopodial ligule anterior]markedly elongate.not markedly elongate.markedly reduced.92. Dorsal notopodial ligule, length on posterior chaetigers [NEXUS: dorsal notopodial ligule posterior]markedly elongate Fig. .not markedly elongate.93. Dorsal notopodial ligule, breadth on posterior chaetigers [NEXUS: dorsal notopodial ligule posterior width]markedly broader Fig. .not markedly broader.94. Dorsal notopodial ligule, reduction on posterior chaetigers [NEXUS: dorsal notopodial ligule posterior size]absent Fig. .markedly reduced.not markedly reduced Fig. .95. Dorsal notopodial ligule (divided into branchiae or not) [NEXUS: dorsal notopodial branchiae]divided into numerous branchial filaments Fig. .not divided into numerous branchial filaments.Dendronereides is the dorsal notopodial ligule divided into numerous branchial filaments. The branchial structures of Dendronereides and Dendronereis are therefore not homologous.Only in 96. Prechaetal notopodial lobe Fig.  smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly.approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes).98. Prechaetal notopodial lobe distribution [NEXUS: prechaetal noto lobe location]present on all chaetigers (may be reduced in size on posterior chaetigers).restricted to a limited number of anterior chaetigers.99. Prechaetal notopodial lobe, reducing in size posteriorly, last present at approx. chaetiger100. Notopodial acicular process .101. Notopodial acicular process reducing in size posteriorly, last present on chaetiger102. Notopodial acicular ligule Fig.  similar to or shorter than neuropodial acicular ligule.prolonged, distinctly longer than neuropodial acicular ligule.reduced, much shorter than neuropodial acicular ligule.104. Dorsal cirrus (divided into branchiae or not) [NEXUS: dorsal cirrus branchiae]divided into numerous branchial filaments Fig. .not divided into numerous branchial filaments.Dendronereis does the dorsal cirrus form numerous branchial filaments. The branchial structures of Dendronereides and Dendronereis are therefore not homologous.Only in 105. Dorsal cirrus Fig.  length o106. Dorsal cirrus: sub-terminally attached to dorsal notopodial ligule on posterior chaetigers, or not [NEXUS: dorsal cirrus subterminal]sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers Fig. .not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.107. Dorsal cirrus terminally attached to dorsal notopodial ligule on posterior chaetigers, or not [NEXUS: dorsal cirrus terminal]terminally attached to dorsal notopodial ligule on posterior chaetigers.not terminally attached to dorsal notopodial ligule on posterior chaetigers.108. Dorsal cirrus terminally attached, or not [NEXUS: dorsal cirrus terminal all]terminally attached throughout, so that dorsal notopodial ligule has appearance of a cirrophore for the dorsal cirrus.not terminally attached throughout all chaetigers.109. Dorsal cirrus (with/without cirrophore) [NEXUS: dorsal cirrophore]simple, lacking basal cirrophore  [NEXUS: dorsal cirrophore expanded]expanded and leaflike , for example in some species of Ceratonereis but we contend that these are misinterpretations.Terminology after 115. Neuropodial prechaetal lobe present on chaetigers116. Neuropodial prechaetal lobe development [NEXUS: neuropodial prechaetal lobe form]projecting beyond postchaetal lobe (at least in anterior chaetigers).not projecting beyond the postchaetal lobe.117. Neuropodial postchaetal lobe .absent.127. Accessory ventral cirrus commencing chaetiger128. Relative length of paired ventral cirri [NEXUS: accessory ventral cirri length]superior ventral cirrus of chaetigers 10–20 longer than inferior cirrus Fig. .superior ventral cirrus of chaetigers 10–20 and inferior cirrus similar in length Fig. .superior ventral cirrus of chaetigers 10–20 shorter than inferior cirrus.Ceratocephale the superior cirrus is always the longer of the pair, especially on the first few chaetigers. However, in at least one species, Ceratocephalepapillata, the superior cirrus is shorter than the inferior cirrus on anterior-most 10–20 chaetigers.In most 129. Notoaciculae on chaetigers 1 and 2 [NEXUS: notoaciculae chaetigers 1 2]present.absent.Ceratonereismirabilis and related species, notoaciculae of chaetigers 1 and 2 are present, but are short and translucent even though those of subsequent chaetigers are dark and extend to the tip of the acicular ligule. Namalycastis and Namanereis have notoacicula in chaetigers 1 and 2, although like notoaciculae in remaining chaetigers, they sit just above the neuroaciculae in the upper part of the neuropodium.Presence of notoaciculae in chaetigers 1 and 2 is difficult to observe and failure to mention this character in published descriptions cannot be taken as evidence of absence. It is necessary to manipulate the parapodia with transmitted light, or, preferably in small specimens, to remove and mount parapodia on slides. In 130. Notochaetae of chaetigers 3 and 4 [NEXUS: notochaetae chaetigers 3 4]present.absent.131. Notochaetae: heterogomph spinigers [NEXUS: notochaetae heterogomph spinigers]present.absent.Chaetal shaft with heterogomph articulation is illustrated in Fig. 132. Notochaetae: homogomph spinigers [NEXUS: notochaetae homogomph spinigers]present.absent.Chaetal shaft with homogomph articulation is illustrated in Fig. 133. Notochaetae: sesquigomph spinigers [NEXUS: notochaetae sesquigomph spinigers]present.absent.Nereididae species before adopting new terms and a revised assessment of their taxonomic significance.Chaetal shaft with sesquigomph articulation is illustrated in Fig. 134. Notochaetae: homogomph falcigers Fig.  distally bifid  Fig.  [NEXUS: present.absent.157. Neurochaetae dorsal fascicle: simple chaetae  present from chaetiger158. Neurochaetae dorsal fascicle: homogomph falcigers in anterior chaetigers [NEXUS: neurochaetae dorsal fascicle homogomph falcigers anterior]present.absent.159. Neurochaetae dorsal fascicle: homogomph falcigers on posterior chaetigers [NEXUS: neurochaetae dorsal fascicle homogomph falcigers posterior]present.absent.160. Neurochaetae ventral fascicle: sesquigomph falcigers [NEXUS: neurochaetae ventral fascicle sesquigomph falcigers]present.absent.161. Neurochaetae ventral fascicle: sesquigomph falcigers blade [NEXUS: neurochaetae ventral fascicle sesquigomph falcigers bifid]distally bifid.with a single distal tooth.162. Neurochaetae ventral fascicle: heterogomph spinigers [NEXUS: neurochaetae ventral fascicle heterogomph spinigers]present.absent.163. Neurochaetae ventral fascicle: heterogomph spinigers in anterior chaetigers with blades [NEXUS: neurochaetae ventral fascicle heterogomph spinigers anterior serrated]evenly serrated throughout.coarsely serrated proximally.164. Neurochaetae ventral fascicle: heterogomph spinigers on posterior chaetigers with blades [NEXUS: neurochaetae ventral fascicle heterogomph spinigers posterior serrated] /finely serrated proximally.coarsely serrated proximally.165. Neurochaetae ventral fascicle: homogomph spinigers [NEXUS: neurochaetae ventral fascicle homogomph spinigers]present.absent.166. Neurochaetae ventral fascicle: sesquigomph spinigers [NEXUS: neurochaetae ventral fascicle sesquigomph spinigers]present.absent.167. Neurochaetae ventral fascicle: heterogomph falcigers [NEXUS: neurochaetae ventral fascicle heterogomph falcigers]present.absent.168. Neurochaetae ventral fascicle: heterogomph falcigers blade [NEXUS: neurochaetae ventral fascicle heterogomph falcigers bowed]tapering, with straight margin Fig. .bowed, with convex margin Fig. .Composetia and similar taxa. Other Nereididae, for example many species illustrated in This character was introduced by 169. Neurochaetae ventral fascicle: anterior chaetigers heterogomph falcigers with long blades Fig.  [NEXUS: present.absent.Definitions of blade length of falcigers were introduced by 170. Neurochaetae ventral fascicle: anterior chaetigers heterogomph falcigers with extra-long blades Fig.  [NEXUS: present.absent.The term “extra-long blades” is equivalent to “Type 1” of 171. Neurochaetae ventral fascicle: anterior chaetigers heterogomph falcigers with short blades Fig.  [NEXUS: present.absent.The term “short blades” is equivalent to “Type 2” of 172. Neurochaetae ventral fascicle: posterior chaetigers heterogomph falcigers with long blades [NEXUS: neurochaetae ventral fascicle heterogomph falcigers posterior long]present.absent.173. Neurochaetae ventral fascicle: posterior chaetigers heterogomph falcigers with extra-long blades [NEXUS: neurochaetae ventral fascicle heterogomph falcigers posterior xlong]present.absent.174. Neurochaetae ventral fascicle: posterior chaetigers heterogomph falcigers with short blades [NEXUS: neurochaetae ventral fascicle heterogomph falcigers posterior short]present.absent.175. Neurochaetae ventral fascicle: heterogomph falcigers blade [NEXUS: neurochaetae ventral fascicle heterogomph falcigers tendon]with recurved terminal tooth and distinct tendon.lacking distinct tendon on terminal tooth.176. Neurochaetae ventral fascicle: heterogomph falcigers blade [NEXUS: neurochaetae ventral fascicle heterogomph falcigers bifid]terminally bifid.with a single terminal tooth.177. Neurochaetae ventral fascicle: homogomph falcigers in anterior chaetigers [NEXUS: neurochaetae ventral fascicle homogomph falcigers anterior]present.absent.178. Neurochaetae ventral fascicle: homogomph falcigers on posterior chaetigers [NEXUS: neurochaetae ventral fascicle homogomph falcigers posterior]present.absent.Namanereis while other Namanereidinae, and some Nicon species, have a bilobate pygidium. Other nereidids are commonly described as having a funnel-shaped pygidium, which may be crenulated or multi-incised (perhaps indicating specimens approaching epitoky). For the majority of Nereididae the form of the pygidium is unknown, often because specimens were incomplete posteriorly. Thus, we have not included a character describing the form of the pygidium.A trilobate pygidium is present in 179. Anal cirri form [NEXUS: anal cirri form]cirriform or conical.short, stout and appearing as an extension of the pygidium.flattened, resembling posterior dorsal cirri.Although some epitokal features may be diagnostic at the genus level , they ar180. Dorsal cirrophores of chaetigers 5–7 of epitokes [NEXUS: dorsal cirrophores chaetigers 5 7]unmodified.modified into flattened elytriform discs.modified into spherical globular structures.181. Natatory region in males commences chaetiger182. Natatory region in males comprises number of chaetigers183. Natatory region in females commences chaetiger184. Natatory region in females comprises number of chaetigers185. Pygidium of male epitokes [NEXUS: pygidium of male epitokes]unmetamorphosed.with pygidial rosette.Male epitokes may have the pygidium modified to form a pygidial rosette with multiple rows of short papillae. The unmodified form is illustrated by 186. Oocyte shape [NEXUS: oocyte form]spherical.ovoid.Nereididae but in many Namanereis species they are ovoid.Oocytes are typically spherical in Nereididae genera are widely recognised as likely para- or polyphyletic groups. They are polymorphic for characters which distinguish other nereidid genera and therefore key out in more than one couplet.It is easy to reach an incorrect identification using a linear  key – one always reaches a name, irrespective of errors that may have been made. Thus, it is wise to doubt, and some form of verification is highly desirable. Our recommendation is that after reaching a genus determination using the key below, the next step should be to compare the specimen at hand with the diagnosis of the genus that has been tentatively identified; if specimen and diagnosis match, the user can have increased confidence in the identification. See Methods above for further discussion. As discussed in the Introduction, several Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 18654014296E-D3B4-5F7C-AE98-5B931F1C5C2DNereis (Alitta) auctt.Nereisvirens Sars, 1835.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=234848.Dorsal notopodial ligule markedly broader on posterior chaetigers; palpophore massive subconical, flattened ; ventral peristomial flap absent; notochaetae sesquigomph spinigers absent .Palpophore massive subconical, flattened . Palpophore surface with a single transverse groove  or with several oblique grooves or striae ; palpostyles subconical. Prostomium anterior margin entire. Tentacular belt greater than length of chaetiger 1. Tentacular cirri cirrophores present.Jaws with dentate cutting edge.A.virens species complex); II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV smooth bar-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present; with Areas V, VI, and VII-VIII discrete. Oral ring pyramidal paragnaths absent, or present. Area V conical paragnaths present, or absent; arranged in a longitudinal line, or irregularly. Area VI paragnaths present; paragnaths arranged in a roughly circular group, or in lines or arcs; conical paragnaths present. Areas VII-VIII paragnaths present; conical paragnaths present; P-bar paragnaths absent, or present.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present ; present on all chaetigers. Notopodial acicular process absent. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; present throughout all chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 present, or absent. Notochaetae of chaetigers 3 and 4 present. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; dorsal fascicle heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present, or absent. Neurochaetae ventral fascicle: heterogomph spinigers present; spinigers in anterior chaetigers with blades evenly serrated throughout; on posterior chaetigers with blades finely serrated proximally; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent; ventral fascicle heterogomph falcigers blade with recurved terminal tooth and distinct tendon, or lacking distinct tendon on terminal tooth; ventral fascicle heterogomph falcigers blade with a single terminal tooth.Anal cirri form cirriform or conical.Alitta is due to Alitta now contains eight species all occurring in either the North Pacific or North Atlantic Oceans. Alittasuccinea  has been reported as a supposed introduced species from numerous cosmopolitan localities but as summarised by The modern concept of Alitta but the four species in the A.virens species complex can be identified using the keys to atokes and to epitokes in There is no identification guide for all species of Taxon classificationAnimaliaPhyllodocidaNereididaeHartman, 19548974DE78-DD2F-5644-B6AF-320764DC6F52Nereis (Leonnates) ehlersi Augener, 1913.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324844.Ventrum of anterior chaetigers with rows of tubercles extending to the base of each neuropodium . Dorsal notopodial ligule commences chaetiger 1; prostomium anterior margin entire; maxillary ring of pharynx with papillae present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Ventrum of anterior chaetigers with rows of tubercles extending to the base of each neuropodium.Maxillary ring of pharynx with papillae present (sometimes with horny tips); solitary; 50–110 papillae in total. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 1; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; digitiform. Ventral neuropodial ligule of anterior chaetigers present.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; sesquigomph spinigers present. Neurochaetae dorsal fascicle: sesquigomph falcigers present; blades serrated; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: sesquigomph falcigers present; heterogomph spinigers absent; homogomph spinigers absent; sesquigomph spinigers present; heterogomph falcigers absent.Anal cirri form cirriform or conical.Australonereis is a monotypic genus. The single species A.ehlersi  occurs only in southern Australian estuaries where these large and often locally abundant worms are instantly recognisable by the conspicuous rows of tuberculae on the ventral surface; living specimens are also much more fragile than those belonging to other genera of Nereididae and readily fragment in the field.Taxon classificationAnimaliaPhyllodocidaNereididaeMalmgren, 1867749B279B-4CAE-58B9-B050-FACE11B61DB7Chaunorhychus Chamberlin, 1919.Pisionura Hartman & Fauchald, 1971.Ceratocephaleloveni Malmgren, 1867.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129371.Transverse dorsal lamellae present; dorsal notopodial ligule absent . Dorsal cirrus arising from basal cirrophore; dorsal notopodial ligule commences chaetiger 3 (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpostyles subconical, or acutely conical. Eyes present, or absent. Prostomium anterior margin indented. Tentacular belt equal to or less than length of chaetiger 1.Jaws with dentate cutting edge.Ceratocephale spp., Areas V and VI contain up to three papillae in total; these are here interpreted as all occurring in Area V, with VI = 0,0.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V three papillae present (close together); VI papillae present, or absent; VII-VIII seven papillae present, arranged in a single row. Oral ring paragnaths absent. In C.abyssorum); commencing chaetiger 4–10.Transverse dorsal lamellae present  based on C.bansei Khlebovich, 1966 may be the only species of Ceratocephale with papillae on Area VI of the pharynx.The definition of Ceratocephale currently includes 12 accepted species recorded from all oceans except the Arctic Ocean and from intertidal to abyssal depths  auctt.Ceratonereismirabilis Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129372.Notochaetae: sesquigomph falcigers present; dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers . Neurochaetae dorsal fascicle: sesquigomph falcigers present; palpophore barrel-shaped, approximately equal width from base to palpostyle  (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle  (elongate). Palpophore surface with a single transverse groove . Prostomium anterior margin indented.Oesophageal caeca absent.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Area I conical paragnaths absent; II conical paragnaths present; III conical paragnaths present; IV paragnaths present; IV conical paragnaths present. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers, or not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers; arising from basal cirrophore; cirrophore of dorsal cirrus short, at most as long as ventral notopodial ligule, or much longer than ventral notopodial ligule; cirrophore of dorsal cirrus not enlarged and vascularised; cirrophore of dorsal cirrus cylindrical throughout.Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform or flattened. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers absent; sesquigomph spinigers present; sesquigomph falcigers present; blade distally bifid, or with a single distal tooth. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers absent; sesquigomph spinigers present; sesquigomph falcigers present; heterogomph falcigers in anterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth; heterogomph falcigers blade terminally bifid, or with a single terminal tooth.Anal cirri form cirriform or conical.Ceratonereis as currently defined follows the concept of Ceratonereis sensu lato”) had included unrelated nereidid species with superficially similar paragnath configuration. Those disparate species (none of which have the indented prostomium characteristic of Ceratonereis sensu stricto) are now moved to genera ComposetiaSimplisetiaCeratonereis is probably monophyletic . Areas VII-VIII conical paragnaths differentiated, with a separate band of minute paragnaths also present; dorsal notopodial ligule markedly broader on posterior chaetigers (secondary diagnosis).Palpophore massive subconical, flattened . Tentacular belt greater than length of chaetiger 1. Ventral peristomial flap present.Oesophageal caeca present.Jaws with dentate cutting edge.C.peristomialis).Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present; II conical paragnaths present; IV paragnaths present; IV conical paragnaths present. Oral ring papillae absent. Oral ring paragnaths present; with Areas V, VI and VII-VIII discrete; on Area V and VI form distinct groups. Area V conical paragnaths absent. Area VI paragnaths present; paragnaths arranged in a roughly circular group; conical paragnaths present; smooth bars absent. Areas VII-VIII paragnaths present; conical; arranged in isolated patches, or in one or more irregular lines forming a continuous band; conical paragnaths differentiated, with a separate band of minute paragnaths also present  from the NW Pacific and C.peristomialis Benham, 1916 from the SE Pacific; both species are commensals of hermit crabs. Cheilonereis species are characterised by the presence of a ventral collar or flap that partly covers the ventral paragnaths of the oral ring when the pharynx is extended  Hartmann-Schröder, 1985.Nereiscostae Grube, 1840.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324848.Neurochaetae ventral fascicle homogomph spinigers present; maxillary ring paragnaths present; oral ring paragnaths absent; Neurochaetae dorsal fascicle: heterogomph falcigers in anterior chaetigers absent; oesophageal caeca present .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Prostomium longitudinal groove present; anterior region entire, sub-quadrangular, longitudinal groove present; prostomial posterior region subequal to or longer than anterior region. Tentacular belt greater than length of chaetiger 1.Oesophageal caeca present.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; IV paragnaths present; IV conical paragnaths present. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; present on all chaetigers, or restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers present; falcigers blade tapering, with straight margin; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth; homogomph falcigers on posterior chaetigers present, or absent.Anal cirri form cirriform or conical.Composetia of Composetia sensu Hartmann-Schröder, 1985 to two new genera: Parasetia and Potamonereis. Composetia currently includes 11 species which collectively are widely distributed around the globe; however, many species have not yet been re-evaluated against the revised concept of The description here follows the revised concept of The only identification guide is the tabular comparisons of Taxon classificationAnimaliaPhyllodocidaNereididaeSouthern, 1921DF13E0A3-B540-593F-9BB4-3AAC46C1AD2EDendronereidesheteropoda Southern, 1921.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=206894.Dorsal notopodial ligule divided into numerous branchial filaments .Ventral neuropodial ligule of anterior chaetigers absent; maxillary ring of pharynx with papillae present; prostomium anterior margin entire (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove .Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae present; solitary. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae present; VI papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule present. Dorsal notopodial ligule divided into numerous branchial filaments. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent.Notochaetae: homogomph spinigers present; sesquigomph spinigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent; homogomph spinigers present; sesquigomph spinigers present, or absent; heterogomph falcigers in anterior chaetigers present, or absent; homogomph falcigers in anterior chaetigers present, or absent. Neurochaetae ventral fascicle: heterogomph spinigers present, or absent; homogomph spinigers present, or absent; heterogomph falcigers present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth; homogomph falcigers on posterior chaetigers present, or absent.Dendronereides is the only nereidid genus in which the dorsal notopodial ligule is transformed into “branchial” filaments; the genus contains three species which occur in tropical estuaries of the Indo-Pacific. There is no taxonomic review or identification guide for the species of Dendronereides.Taxon classificationAnimaliaPhyllodocidaNereididaePeters, 18541A17B1DC-9FC4-5F1C-87C5-87884ACDA302Dendronereisarborifera Peters, 1854.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=206700.Dorsal cirrus divided into numerous branchial filaments . Ventral neuropodial ligule on posterior chaetigers absent; palpophore massive subconical, flattened ; prostomium anterior margin indented (secondary diagnosis).Palpophore massive subconical, flattened . Prostomium anterior margin indented.Maxillary ring of pharynx with papillae present, or absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly. Dorsal cirrus divided into numerous branchial filaments. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers absent. Neuropodia of branchial chaetigers divided into five lobes, plus ventral cirrus, plus two smaller cirri on ventral neuropodial lobe . Posteriorly becoming simpler, eventually with a single neuropodial lobe and ventral cirrus.Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers absent.Dendronereis are easily recognised as this is the only genus of Nereididae in which the dorsal cirrus is transformed into branchial filaments. Species belonging to Dendronereis are known, all occurring in shallow waters of the Indo-Pacific. Five species of Taxon classificationAnimaliaPhyllodocidaNereididaeMalmgren, 18652D3814AB-6658-59B9-99B3-E5B5DDB85B41Nereis (Eunereis) Malmgren, 1865.Nereislongissima Johnston, 1840.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129373.Oral ring paragnaths present; maxillary ring paragnaths absent .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present, or absent. Oral ring paragnaths present; with Areas V, VI, and VII-VIII discrete, or comprising a continuous ring dorsally and ventrally, discrete groups not recognisable; on Areas V and VI form distinct groups. Area V conical paragnaths present, or absent. Area VI paragnaths present; arranged in a roughly circular group; conical paragnaths present, or absent; smooth bars present, or absent. Areas VII-VIII paragnaths present, or absent; conical paragnaths present; conical paragnaths arranged in isolated patches, or in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers, or not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process present, or absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers; simple, lacking basal cirrophore.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade tapering, with straight margin; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Composetia) by The description here follows Eunereis is the only Nereididae genus with paragnaths present only on the oral ring. Eunereis includes species which in other respects, especially chaetal characters, are similar to either of the genera Neanthes or Nereis suggesting a review is necessary.Eunereis includes ten accepted species which encompass wide geographic and bathymetric distributions. There is no published identification guide to all species.Taxon classificationAnimaliaPhyllodocidaNereididaeHorst, 19193018967B-9FEF-5D04-B384-F9791C2CB15BGymnorhynchus Horst, 1919 (replaced homonym).Gymnorhynchussibogae Horst, 1918.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324851.Accessory ventral cirrus present; neurochaetae ventral fascicle sesquigomph spinigers present . Notochaetae sesquigomph spinigers present; dorsal notopodial ligule present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove ; palpostyles subconical, or acutely conical. Prostomium anterior margin indented.Jaws with smooth or slightly crenulate cutting edge or with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae present; VI papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Transverse dorsal lamellae absent, or present.Dorsal notopodial ligule present; commences chaetiger 1; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers . Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; present on all chaetigers. Notopodial acicular process present. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers; arising from basal cirrophore.Neuropodial prechaetal lobe present; extending beyond postchaetal lobe (at least in anterior chaetigers). Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; present throughout all chaetigers; flattened. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule. Accessory ventral cirrus present.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present, or absent; sesquigomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present, or absent; sesquigomph spinigers present. Neurochaetae dorsal fascicle: sesquigomph falcigers present, or absent; blades serrated; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: sesquigomph falcigers present, or absent; heterogomph spinigers absent; homogomph spinigers present, or absent; sesquigomph spinigers present; heterogomph falcigers absent.Anal cirri form cirriform or conical.Gymnonereis is diagnosed by the presence of accessory dorsal and ventral cirri and notochaetae comprising sesquigomph spinigers . There is no published key to all species although several regional keys exist  Malmgren, 1867.Nereisdiversicolor Müller, 1776.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=146968.Neurochaetae dorsal fascicle simple chaetae  present; palpophore massive subconical, flattened  .Palpophore massive subconical, flattened . Palpophore surface with a single transverse groove . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present; with Areas V, VI, and VII-VIII discrete; on Areas V and VI form distinct groups. Area V conical paragnaths absent. Area VI paragnaths present; paragnaths arranged in a roughly circular group, or in lines or arcs; conical paragnaths present; smooth bars absent. Area VII-VIII paragnaths present; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; simple chaetae  present. Neurochaetae ventral fascicle: heterogomph spinigers present or absent; homogomph spinigers absent; homogomph falcigers present or absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Hediste species are characterised by the “simple” neuropodial falcigers (with fused articulation) which are present in posterior chaetigers and by having paragnaths on both rings of the pharynx. The most recent taxonomic treatments are Hediste is a genus of estuarine nereidids which occur in the northern hemisphere. Seven species of Hediste are currently described but despite recent publications, the most widespread species, H.diversicolor  still contains cryptic species not yet described . Neurochaetae dorsal fascicle heterogomph falcigers in anterior chaetigers absent; Area VI papillae absent; palpophore barrel-shaped, approximately equal width from base to palpostyle  (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI papillae absent; VII-VIII papillae present. Oral ring paragnaths present; with Areas V, VI, and VII-VIII discrete; on Areas V and VI form distinct groups. Area V conical paragnaths absent. Area VI paragnaths present; paragnaths arranged in a roughly circular group; conical paragnaths present; smooth bars absent. Areas VII-VIII paragnaths present; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe present. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers present; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades absent; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent.Imajimainereis contains a single species, I.pacifica de León-González & Solís-Weiss, 2000, which differs from all other Nereididae by having both papillae and paragnaths on the oral ring and neurochaetae including heterogomph spinigers.Imajimainereis is recorded from the Gulf of California, eastern Pacific Ocean . Notochaetae homogomph falcigers present; maxillary ring paragnaths absent; oral ring paragnaths absent; dorsal notopodial ligule not markedly reduced on posterior chaetigers (secondary diagnosis).Palps anteriorly directed, or ventrally directed. Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium the antennae are separate but sometimes basally fused in male epitokes. Tentacular cirri articulated.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring paragnaths absent.Dorsal notopodial ligule commences chaetiger 3, or chaetiger 4 ; not markedly elongate on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present . Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; present throughout all chaetigers. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present ; homogomph falcigers with multidentate blade with two or more small lateral teeth, first and subsequent lateral teeth much smaller than terminal tooth present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade bowed, with convex margin.Pygidium bilobate. Anal cirri form cirriform or conical.Dorsal cirrophores of chaetigers 5–7 of epitokes modified into flattened elytriform discs. Natatory epitokal modifications in males commence chaetiger 15. Natatory epitokal modifications in females commence chaetiger 15.Kainonereis was originally described for an epitokous specimen in which dorsal cirri of chaetigers 5–7 were expanded into elytra-like structures. Unless epitokes are available Kainonereis is not separable from Nicon and Websterinereis . A revision by Taxon classificationAnimaliaPhyllodocidaNereididaePettibone, 1971A548C2F2-63AF-5B86-936E-156FC2B5648DNereis (Leptonereis) inermis Hoagland, 1920.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=843657.Neurochaetae ventral fascicle heterogomph spinigers in anterior chaetigers with blades coarsely serrated proximally; oral ring papillae present; maxillary ring of pharynx with papillae absent . Prostomium anterior margin indented; prechaetal notopodial lobe approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes); antennae form cirriform ; maxillary ring paragnaths absent (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle  (elongate). Prostomium anterior margin indented.Jaws with dentate cutting edge, 20 teeth.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae number two in total; arrangement solitary. Area V papillae absent; VI papillae present, one papilla (a single fleshy nob on each side); VII-VIII papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes); present on all chaetigers. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial prechaetal lobe present. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; flattened. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers present; spinigers in anterior chaetigers with blades coarsely serrated proximally; homogomph spinigers absent; heterogomph falcigers absent.Kinberginereis is the original description of Kinberginereis is most similar to Kainonereis, atokes differing only in that Kinberginereis has an indented prostomium but the prostomium of Kainonereis is entire. Epitokes of Kainonereis are distinctive in having elytriform expansion of dorsal cirrophores of chaetigers 5–7 but epitokes of Kinberginereis are unknown.The most recent taxonomic treatment of Kinberginereis includes a single species, K.inermis  described from a single specimen from shallow water in the Philippines; the only subsequent reports are unverified occurrence records now in the Smithsonian National Museum of Natural History from the Gulf of Mexico.Taxon classificationAnimaliaPhyllodocidaNereididaeHartman, 19458C7A0D76-6047-5EB7-B63D-A6B04E21F426Nereisculveri Webster, 1879.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=181592.Maxillary ring of pharynx with papillae in tufts . Dorsal notopodial ligule commences chaetiger 1; neurochaetae ventral fascicle homogomph falcigers on posterior chaetigers present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented; longitudinal groove present.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae present; in tufts. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI papillae present; VII-VIII papillae present or absent (may be absent in juveniles). Oral ring paragnaths absent. Papillae triangular or conical on Area VI, rounded on Areas VII-VIII.Dorsal notopodial ligule present; commences chaetiger 1; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent; homogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers absent; homogomph falcigers on posterior chaetigers present (with long blades).Pygidium funnel-shaped, crenulated, or multi-incised, with ventral incision. Anal cirri cirriform or conical.Laeonereis here is derived from the revision of Laeonereis. Simultaneously with the publication of the morphological revision of Laeonereis by Laeonereis  and revealed seven or nine molecular OTUs. It is tantalising that The description and diagnosis of Laeonereis are recognised, largely confined to the Atlantic coasts of North and South America; they can be identified using the key of Currently eight species of Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 1865C3644EC1-EA46-55DC-A616-A86BEEAC1EA8Nereis (Leonnates) auctt.Laevispinereis He & Wu, 1989.Leonnatesindicus Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129374.Oral ring papillae present; maxillary ring paragnaths present; oral ring paragnaths absent; ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule; neurochaetae dorsal fascicle homogomph spinigers present .L.persicus and L.stephensoni); longitudinal groove present; anterior region sub-quadrangular or sub-rectangular. Tentacular belt greater than length of chaetiger 1.Palpophore barrel-shaped, approximately equal width from base to palpostyle , or massive subconical, flattened . Palpophore surface with a single transverse groove . Prostomium anterior margin entire or indented ; present on all chaetigers, or restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; present throughout all chaetigers or restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.L.fujianensis); homogomph spinigers present; sesquigomph spinigers present, or absent (present in L.fujianensis); sesquigomph falcigers present, or absent; heterogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent; homogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent. Neurochaetae ventral fascicle: sesquigomph falcigers present, or absent; blade with a single distal tooth; heterogomph spinigers present, or absent; homogomph spinigers present, or absent; sesquigomph spinigers present, or absent; heterogomph falcigers present, or absent; falcigers blade bowed, with convex margin; heterogomph falcigers blade lacking distinct tendon on terminal tooth; homogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent. Ventral fascicle neuropodial falcigers apparently vary considerably between species.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent , 5E , 7B , 9D  all show sesquigomph articulation as accepted by other authors, e.g. Parasetiairritabilis ), Leonnatescrosnieri de León-González & Salazar-Vallejo, 2003).The current description and diagnosis follow Leonnates includes 13 species with the greatest diversity in the tropical Indo-Pacific. Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 1865BD8300F9-84E4-5EEF-A4DA-55C68B821E5BNereis (Leptonereis) auctt.Leptonereislaevis Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=152401.Dorsal cirrus terminally attached to dorsal notopodial ligule on posterior chaetigers; maxillary ring paragnaths absent . Dorsal notopodial ligule markedly broader on posterior chaetigers; prostomium anterior margin entire; maxillary ring of pharynx with P-bar paragnaths absent (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle .Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; markedly elongate on posterior chaetigers; markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notochaetae: homogomph spinigers present. Neurochaetae homogomph and heterogomph spinigers and heterogomph falcigers, but their distribution in dorsal and ventral fascicles is unknown.Leptonereis given here follows the most recent treatment  . Neurochaetae dorsal fascicle homogomph falcigers on posterior chaetigers present; maxillary ring paragnaths absent; prostomium anterior margin entire (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Prostomium anterior margin entire. Tentacular belt greater than length of chaetiger 1. Tentacular cirri three pairs.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae present. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI papillae present; VII-VIII papillae present, arranged in a single row. Oral ring paragnaths absent.Dorsal notopodial ligule markedly reduced or absent on posterior chaetigers. Prechaetal notopodial lobe present; restricted to a limited number of anterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; dorsal fascicle heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent; dorsal fascicle homogomph falcigers in anterior chaetigers present; on posterior chaetigers present; ventral fascicle heterogomph spinigers absent; homogomph spinigers present; sesquigomph spinigers present. Neurochaetae ventral fascicle: heterogomph falcigers absent; homogomph falcigers in anterior chaetigers present; on posterior chaetigers present.This easily diagnosed genus from estuaries in India includes a single species. Taxon classificationAnimaliaPhyllodocidaNereididaeDay, 19630FD2B90F-6BE2-5215-9ADB-53D8CB09F980Micronereidescapensis Day, 1963.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324861.Tentacular belt represented by two distinct segments each carrying a pair of tentacular cirri . Dorsal notopodial ligule absent; neurochaetae ventral fascicle sesquigomph spinigers present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Eyes absent. Prostomium with eyes, if not absent, indistinct and likely to be missed. Tentacular belt equal to or less than length of chaetiger 1; represented by two distinct segments each carrying a pair of tentacular cirri.Jaws with dentate cutting edge, seven teeth.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule absent. Prechaetal notopodial lobe absent. Notopodial acicular process absent.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers short, up to half length of acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule. Dorsal notopodial ligule elongate, exceeding length of dorsal cirrus.Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent; ventral fascicle heterogomph spinigers absent; homogomph spinigers present; sesquigomph spinigers present .Micronereides was erected to contain M.capensis Day, 1963 a small nereidid lacking pharyngeal papillae or paragnaths and in which tentacular cirri arise from two distinct anterior segments (unique among Nereididae). A revised diagnosis was provided by Gymnonereidinae.M.capensis, recorded from shelf depths in the South Atlantic Ocean.The genus is still only known from a single species, Taxon classificationAnimaliaPhyllodocidaNereididaeClaparède, 1863B54F0B95-D187-5F51-B03F-00845FCB5AD9Notophycus Knox & Cameron, 1970.Phyllodocella Fauchald & Belman, 1972.Quadricirra Banse, 1977.Micronereisvariegata Claparède, 1863.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129375.Palpostyles absent  . Maxillary ring of pharynx undivided (secondary diagnosis).Antennae absent. Palps ventrally directed. Palpophore surface with a single transverse groove ; palpostyles absent .Jaws with dentate cutting edge.Maxillary ring of pharynx undivided.Maxillary ring of pharynx with papillae absent; undivided maxillary ring with two paragnaths in total. Oral ring papillae absent. Oral ring paragnaths present; on Areas V and VI not recognisably distinct. Crown-shaped oral ring paragnaths present. Area V conical paragnaths absent.Dorsal notopodial ligule absent. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Acicular notopodial ligule absent.Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent.M.bansei). Notochaetae: homogomph spinigers present; homogomph falcigers present or absent; homogomph falcigers with multidentate blade with two or more small lateral teeth, first and subsequent lateral teeth much smaller than terminal tooth present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; homogomph falcigers in anterior chaetigers present; on posterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers absent.Notoaciculae on chaetigers 1 and 2 absent  marine waters. Micronereis species differ from other Nereididae in lacking antennae and having a pharynx that is not fully eversible. They are sexually dimorphic and males have distinctive neurochaetae that function as copulatory hooks not found in other Nereididae.Micronereis currently includes ten accepted species which collectively have a wide global distribution. Taxon classificationAnimaliaPhyllodocidaNereididaeHartman, 1959C39C0DA3-0F57-5783-89CE-D206253F0F3CLycastisabiuma Grube, 1872.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129376.Palpophore surface without grooves or striae ; antennae form subconical  . Prostomium anterior margin indented (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface without grooves or striae  or with a single transverse groove ; palpostyles spherical. Prostomium anterior margin indented; longitudinal groove present. Tentacular belt equal to or less than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Notopodium strongly reduced, without distinct lobes or ligules. Dorsal cirrus arising from basal cirrophore .Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers absent; sesquigomph spinigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers present (rarely), or absent; homogomph spinigers absent; sesquigomph spinigers present; heterogomph falcigers in anterior chaetigers present, or absent (rarely); on posterior chaetigers present, or absent; blades smooth, or serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present; spinigers in anterior chaetigers with blades evenly serrated throughout, or coarsely serrated proximally (rarely); on posterior chaetigers with blades finely serrated proximally, or coarsely serrated proximally; homogomph spinigers absent; heterogomph falcigers present, or absent (rarely); anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent.Pygidium with three incisions marking lateral and dorsal lobes. Anal cirri form cirriform or conical, or flattened, resembling posterior dorsal cirri.Oocyte spherical.Namalycastis currently includes 33 accepted species recorded mainly from intertidal and supralittoral areas, including freshwater, of the tropics and subtropics. Together with sister-group Namanereis, they are one of only a few polychaetes to be found in association with riparian vegetation. Because they have an unadorned pharynx and a simplified parapodia, distinguishing species relies heavily on differences in chaetae, form of sensory organs of the head, and pigmentation patterns in living specimens. The modern concept of the subfamily and genus was introduced by Namalycastiscaetensis Alves & Santos, 2016, Namalycastisglasbyi Fernando & Rajasekaran, 2007, Namalycastisjaya Magesh, Kvist & Glasby, 2012, Namalycastisocculta Conde-Vela, 2013 and Namalycastisrhodochorde Glasby, Miura, Nishi & Junardi, 2007; however, Namalycastisocculta Conde-Vela, 2013 is now accepted as Namanereisocculta . Taxon classificationAnimaliaPhyllodocidaNereididaeChamberlin, 1919E4E1CB01-7AE5-5147-9A46-E3FB005E109ECryptonereis Gibbs, 1971.Lycastella Feuerborn, 1932.Lycastilla Solís-Weiss & Espinasa, 1991.Lycastoides Jakubova, 1930.Lycastopsis Augener, 1922.Lycastisquadraticeps Blanchard in Gay, 1849.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129377.Palpophore surface without grooves or striae ; prostomium anterior margin entire . Palpostyles spherical; dorsal cirrus simple, lacking basal cirrophore (secondary diagnosis).Antennae present, or absent (rarely). Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface without grooves or striae  or with a single transverse groove ; palpostyles spherical. Eyes present, or absent. Tentacular belt equal to or less than length of chaetiger 1. Tentacular cirri four pairs, or three pairs.Jaws forms with a crenulate cutting edge have 2 teeth proximally, with smooth or slightly crenulate cutting edge or with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Notopodium strongly reduced, without distinct lobes or ligules.Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers absent; sesquigomph spinigers present (rarely), or absent. Neurochaetae dorsal fascicle: heterogomph spinigers present (rarely), or absent; homogomph spinigers absent; sesquigomph spinigers present, or absent; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally, or much longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present (rarely), or absent; spinigers in anterior chaetigers with blades evenly serrated throughout; on posterior chaetigers with blades finely serrated proximally; homogomph spinigers absent; heterogomph falcigers present (some forms with very long blades = pseudospinigers); anterior chaetigers heterogomph falcigers with long blades present; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades absent.Pygidium with three incisions marking lateral and dorsal lobes. Anal cirri form cirriform or conical, or short, stout and appearing as an extension of the pygidium.Oocyte spherical (rarely), or ovoid.Namanereis currently includes 27 accepted species recorded mainly from intertidal, supralittoral and terrestrial areas, including the freshwaters of streams, caves, and underground aquifers. Although mainly found in the tropics and subtropics one species, Namanereisquadraticeps (Blanchard in Gay 1849), has a circum-subantarctic/temperate distribution. Together with sister-group Namalycastis, they are one of only a few polychaetes to be found in association with riparian vegetation. Because they have an unadorned pharynx and a simplified parapodia, distinguishing species relies heavily on differences in chaetae and form of sensory organs of the head. The modern concept of the subfamily and genus was introduced by Namanereiscanariarum Núñez, Glasby & Naranjo, 2020, Namanereischristopheri Conde-Vela, 2017, Namanereisgesae Fiege & Van Damme, 2002, Namanereisllanetensis Núñez, Glasby & Naranjo, 2020, Namanereisocculta , Namanereispilbarensis Glasby, Fiege & Van Damme, 2014, and Namanereissocotrensis Glasby, Fiege & Van Damme, 2014, making this genus one of the most studied in the last 20 or so years. As noted by Lycastoidesalticola Johnson, 1903 is also part of the Namanereis clade, but the species cannot take the name Namanereis, as Lycastoides is the senior genus  auctt.Nereis (Neanthioides) Rioja, 1918.Praxithea Malmgren, 1867.Neanthesvaalii Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129378.Maxillary ring paragnaths present; neurochaetae dorsal fascicle heterogomph falcigers in anterior chaetigers present; dorsal notopodial ligule not markedly broader on posterior chaetigers; oral ring papillae absent; notochaetae homogomph falcigers absent; notochaetae sesquigomph falcigers absent; neurochaetae dorsal fascicle simple chaetae  absent; Area VI smooth bars absent; notoaciculae on chaetigers 1 and 2 absent .Palpophore barrel-shaped, approximately equal width from base to palpostyle , or massive subconical, flattened  (rarely). Palpophore surface without grooves or striae or with a single transverse groove  or with several oblique grooves or striae . Eyes present, or absent. Tentacular belt greater than length of chaetiger 1.Oesophageal caeca present, or absent.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present; II conical paragnaths present, or absent; III conical paragnaths present, or absent; III rod-like paragnaths absent; IV paragnaths present, or absent; IV conical paragnaths present, or absent; IV smooth bar-like paragnaths present, or absent; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present, or absent; with Areas V, VI, and VII-VIII discrete, or comprising a continuous ring dorsally and ventrally, discrete groups not recognisable; on Areas V and VI form distinct groups, or not recognisably distinct. Area V conical paragnaths present, or absent. Area VI paragnaths present, or absent; paragnaths arranged in a roughly circular group, or in lines or arcs; conical paragnaths present; smooth bars absent. Areas VII-VIII paragnaths present, or absent; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band, or differentiated, with a separate band of minute paragnaths also present; rod-shaped paragnaths absent.Dorsal notopodial ligule markedly elongate on anterior chaetigers, or not markedly elongate on anterior chaetigers; markedly elongate on posterior chaetigers, or not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers, or not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly, or approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes); present on all chaetigers, or restricted to a limited number of anterior chaetigers. Notopodial acicular process present, or absent; reducing in size posteriorly, last present on chaetiger 5–25. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers, or not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule, or not projecting beyond end of the acicular ligule; present throughout all chaetigers, or restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present, or absent. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present, or absent; blades serrated. Neurochaetae ventral fascicle: heterogomph spinigers present, or absent; homogomph spinigers present, or absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades present, or absent; anterior chaetigers heterogomph falcigers with extra-long blades present, or absent; anterior chaetigers heterogomph falcigers with short blades present, or absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Neanthes, even after removing some species to Alitta and Pseudonereis, was found by N.gisserana  and N.glandicincta ) and with elongate dorsal notopodial lobe on all chaetigers , and N.mossambica Day, 1957) or only on posterior chaetigers . Furthermore, Neanthes includes a subset of species having well-developed prechaetal notopodial lobes, giving the notopodia a tri-lobed appearance, which differs from the majority of bilobed species  oxypoda Marenzeller, 1879.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324862.Dorsal notopodial ligule markedly broader on posterior chaetigers; notochaetae sesquigomph spinigers present . Palpophore massive subconical, flattened ; neurochaetae dorsal fascicle heterogomph spinigers present (secondary diagnosis).Palpophore massive subconical, flattened .Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring paragnaths present; with Areas V, VI and VII-VIII discrete; on Areas V and VI form distinct groups. Area V conical paragnaths present. Area VI paragnaths present; paragnaths arranged in a roughly circular group; conical paragnaths present; smooth bars absent. Areas VII-VIII paragnaths present; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule markedly elongate on posterior chaetigers; markedly broader on posterior chaetigers. Prechaetal notopodial lobe present; approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes); present on all chaetigers. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on anterior or posterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; present throughout all chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule. Notopodial dorsal ligule with prominent ovoid lobe medial to the dorsal cirrus in middle and posterior parapodia.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers present; sesquigomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present; homogomph spinigers present; sesquigomph spinigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers present; heterogomph falcigers present ; falcigers blade tapering, with straight margin; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent.Anal cirri form cirriform or conical.Nectoneanthes was treated as a synonym of Neanthes by Nectoneanthesoxypoda  as an epitokal form and resurrected Nectoneanthes and described a second species for the genus. The description by Nectoneanthes; both species occur on the north-west Pacific coast, with N.oxypoda also recorded by Taxon classificationAnimaliaPhyllodocidaNereididaeLinnaeus, 175806161371-38D6-527E-A638-D12FF23784E8Heteronereis Örsted, 1843.Johnstonia Quatrefages, 1850.Lycoris Lamarck, 1818.Naumachius Kinberg, 1865.Nereis (Nereis) auctt.Thoosa Kinberg, 1865.Nereispelagica Linnaeus, 1758.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129379.Notochaetae homogomph falcigers present; maxillary ring paragnaths present; Area II rod-like paragnaths absent; dorsal notopodial ligule not markedly elongate on posterior chaetigers; antennae present; oral ring papillae absent .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Eyes present, or absent. Tentacular belt greater than length of chaetiger 1.Oesophageal caeca present, or absent.Jaws with smooth or slightly crenulate cutting edge or with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present, or absent; II conical paragnaths present, or absent; III conical paragnaths present, or absent; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV smooth bar-like paragnaths present, or absent; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present, or absent; Areas V, VI, and VII-VIII discrete, forming distinct groups. Area V conical paragnaths present, or absent; arranged in a triangle, or in a longitudinal line. Area VI paragnaths present, or absent; paragnaths arranged in a roughly circular group; conical paragnaths present; smooth bars absent. Areas VII-VIII paragnaths present, or absent; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers, or not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present, or absent; spinigers in anterior chaetigers with blades evenly serrated throughout; on posterior chaetigers with blades finely serrated proximally; homogomph spinigers absent; heterogomph falcigers present, or absent; anterior chaetigers heterogomph falcigers with long blades present, or absent; anterior chaetigers heterogomph falcigers with extra-long blades present, or absent; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Nereis is the type taxon of the family Nereididae. It is a large assemblage of species, currently with 226 species attributed to the genus, many that probably belong in other genera. There are no revisions of the genus, or parts of it, or any that delineate species into informal subgroups. The description here follows Nereis have been found from the littoral zone to abyssal areas, and from a wide range of habitats.Species of N.falsa de Quatrefages, 1866.No complete identification guide to species is available but several useful keys of restricted scope have been published: Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 1865C0A85013-959C-5B78-B1A0-AD0552B97E0ANiconpictus Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=173735.Maxillary ring paragnaths and papillae absent; neuropodial postchaetal lobe present; dorsal notopodial ligule commences chaetiger 3; dorsal notopodial ligule not markedly reduced on posterior chaetigers; oral ring paragnaths absent; notochaetae homogomph falcigers absent .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Eyes present, or absent. Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae and paragnaths absent. Oral ring papillae and paragnaths absent.Dorsal notopodial ligule present, or absent; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; present throughout all chaetigers, or restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent; blades serrated; simple chaetae  present, or absent; homogomph falcigers in anterior chaetigers present, or absent. Neurochaetae ventral fascicle: sesquigomph falcigers present, or absent; heterogomph spinigers present, or absent; homogomph spinigers present, or absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade with recurved terminal tooth and distinct tendon, or lacking distinct tendon on terminal tooth; homogomph falcigers in anterior chaetigers present, or absent.Pygidium bilobate. Anal cirri form cirriform or conical.Nicon is not a species-rich genus: of the 700+ species of Nereididae, only ten belong to the genus Nicon and those ten species are from diverse habitats and widespread regions . Ventral neuropodial ligule of anterior chaetigers short, up to half length of acicular neuropodial ligule; oral ring papillae present; prostomium anterior margin entire; Area V papillae absent (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae present; solitary. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 3; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers.Neuropodial prechaetal lobe present. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers short, up to half length of acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present; spinigers in anterior chaetigers with blades evenly serrated throughout; on posterior chaetigers with blades finely serrated proximally; homogomph spinigers absent; heterogomph falcigers present; falcigers blade bowed, with convex margin; heterogomph falcigers blade with recurved terminal tooth and distinct tendon.Anal cirri form cirriform or conical.Ceratocephalaedmondsi Hartman, 1954  was separated into the new genus Olganereis by Ceratocephale species).Olganereis is monotypic and the sole species O.edmondsi  occurs in estuaries in southern Australia. The only other Australian nereidid with papillae on both rings of the pharynx is Dendronereidesheteropoda Southern, 1921 from tropical estuaries and in which the dorsal notopodial ligule is divided into 'branchial' filaments.Taxon classificationAnimaliaPhyllodocidaNereididaeKhlebovich & Wu, 19622AF17D19-1FA0-5B81-BE0E-F9C5A8A432D0Ganganereis Misra, 1999.Periserrula Paik, 1977.Paraleonnatesuschakovi Chlebovitsch & Wu, 1962.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324866.Neurochaetae dorsal fascicle homogomph spinigers absent; oral ring papillae present; prostomium anterior margin entire .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove .Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present, or absent; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae present, or absent; VI papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; approximately equal to length of dorsal notopodial ligule at least on anterior chaetigers (thus notopodium of three similar sized ligules/lobes). Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present; homogomph spinigers absent. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth; homogomph falcigers in anterior chaetigers present, or absent; on posterior chaetigers present, or absent.Anal cirri form cirriform or conical.Paraleonnates are those of Paraleonnates is a genus of four species which occur in shallow muddy habitats, typically estuaries and mangroves, in the Indo-Pacific.The most recent taxonomic treatments of Paraleonnates but omits Paraleonnatestenuipalpa  which had been moved to Paraleonnates by P.tenuipalpa may be a senior synonym of Paraleonnatesbolus .Taxon classificationAnimaliaPhyllodocidaNereididaeVillalobos-Guerrero, Conde-Vela & Sato, 20223FAA02AD-6AE1-5EC6-8533-F6B145884B80Nereisirritabilis Webster, 1879.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=1600661.Neurochaetae dorsal fascicle sesquigomph falcigers present; palpophore massive subconical, flattened ; oral ring papillae absent . Neurochaetae ventral fascicle sesquigomph falcigers present; neuropodial postchaetal lobe not projecting beyond end of the acicular ligule (secondary diagnosis).Palpophore massive subconical, flattened . Prostomium longitudinal groove present; anterior region entire, hemispherical, longitudinal groove present; prostomial posterior region as long as anterior region. Tentacular belt greater than length of chaetiger 1.Oesophageal caeca absent.Jaws with smooth or slightly crenulate cutting edge.Everted pharynx a truncate cone, tapering, greatest width at margin of tentacular belt.Maxillary ring paragnaths present. Area I conical paragnaths absent; II conical paragnaths present; III conical paragnaths present; IV paragnaths present; IV conical paragnaths present. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; restricted to a limited number of anterior chaetigers. Notopodial acicular process present, or absent.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; sesquigomph falcigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: sesquigomph falcigers present; heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers absent; falcigers blade bowed, with convex margin.Anal cirri form cirriform or conical.Parasetia was established by Nereisirritabilis Webster, 1878, removed from Composetia due to absence of oesophageal caeca and other morphological differences from a redefined Composetia. Parasetiairritabilis  occurs on the Atlantic coast of North America down to a depth of ~ 50 m.Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 1865085C72C3-6E60-56C1-9E89-8E6F7C7C3512Arete Kinberg, 1865.Gnatholycastis Ehlers, 1920.Lipephile Malmgren, 1867.Nereis (Lipephile) Malmgren, 1867.Nereis (Perinereis) auctt.Perinereisnovaehollandiae Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129380.Palpophore massive subconical, flattened ; oral ring paragnaths present; Area VI smooth bars present; antennae present .Palpophore massive subconical, flattened . Palpophore surface with a single transverse groove . Tentacular belt greater than length of chaetiger 1.Jaws with smooth or slightly crenulate cutting edge or with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present or absent; II conical paragnaths present or absent; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present or absent; IV smooth bar-like paragnaths present, or absent; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present; with Areas V, VI, and VII-VIII discrete; on Areas V and VI form distinct groups. Area V conical paragnaths present, or absent; arranged in a triangle, or in a longitudinal line. Area VI paragnaths present, arranged in lines or arcs; conical paragnaths present, or absent; smooth bars present. Areas VII-VIII paragnaths present, or absent; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; rod-shaped paragnaths absent.Dorsal notopodial ligule markedly elongate on posterior chaetigers, or not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers, or not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule; present throughout all chaetigers, or restricted to anterior chaetigers. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally, or much longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present, or absent; spinigers in anterior chaetigers with blades evenly serrated throughout, or coarsely serrated proximally; on posterior chaetigers with blades finely serrated proximally; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades present, or absent; anterior chaetigers heterogomph falcigers with extra-long blades present, or absent; anterior chaetigers heterogomph falcigers with short blades present, or absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Perinereis contains 97 species and is thus one of the most species-rich in the family  auctt.Platynereismagalhaensis Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129381.Areas VII-VIII rod-shaped paragnaths present . Notochaetae homogomph falcigers with terminal tendon present (secondary diagnosis).Palps anteriorly directed, or ventrally directed. Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area II rod-like paragnaths present; III conical paragnaths absent; III rod-like paragnaths present; IV paragnaths present; IV conical paragnaths absent; IV rod-like paragnaths present. Oral ring papillae present, or absent. Oral ring paragnaths present; on Area V and VI form distinct groups. Area V conical paragnaths absent. Area VI paragnaths present; conical paragnaths absent; rod-shaped paragnaths present. Areas VII-VIII paragnaths present; conical paragnaths absent; conical paragnaths arranged in isolated patches, or in one or more irregular lines forming a continuous band; rod-shaped paragnaths present.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Dorsal cirrus sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present; with terminal tendon present; articulation fused on some chaetigers (present as a simple chaeta), or with blade free throughout. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present; spinigers in anterior chaetigers with blades evenly serrated throughout; on posterior chaetigers with blades finely serrated proximally; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Platynereis are easily recognised by the small rod-like paragnaths in tight rows on the pharynx; 36 species are recognised. No revisions have been published, but regional studies using molecular data to revise species to resolve the complex taxonomy, and taxonomic history of this genus have been appearing .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium longitudinal groove present; anterior region entire, hemispherical, longitudinal groove present; prostomial posterior region shorter than anterior region. Tentacular belt greater than length of chaetiger 1.Oesophageal caeca absent.Jaws with dentate cutting edge.Everted pharynx a truncate cone, tapering, greatest width at margin of tentacular belt.Maxillary ring paragnaths present. Area I conical paragnaths present, or absent; II conical paragnaths present; III conical paragnaths present; III conical paragnaths isolated lateral groups absent; IV paragnaths present; IV conical paragnaths present. Oral ring paragnaths absent.Prechaetal notopodial lobe absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade tapering, with straight margin.Anal cirri form cirriform or conical.Potamonereis was established by Composetia in which oesophageal caeca are absent and which have a truncate-conical pharynx, and other morphological differences (at the same time those authors redefined Composetia). Both species of Potamonereis occur in the North-west Pacific in Japanese estuaries.Taxon classificationAnimaliaPhyllodocidaNereididaeKinberg, 1865CB56277D-22CA-5D26-8542-5AED85FC6614Phyllonereis Hansen, 1882.Pseudonereisgallapagensis Kinberg, 1865.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=129382.Maxillary ring of pharynx with P-bar paragnaths present, usually in regular comb-like rows . Area VI shield-shaped bars present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present; of pharynx with P-bar paragnaths present, usually in regular comb-like rows. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths present; with Areas V, VI and VII-VIII discrete; on Area V and VI form distinct groups. Area V conical paragnaths present, or absent. Area VI paragnaths present; paragnaths arranged in lines or arcs; conical paragnaths present, or absent; smooth bars present, or absent; shield-shaped bars present. Areas VII-VIII paragnaths present; conical paragnaths present; conical paragnaths arranged in one or more irregular lines forming a continuous band; conical paragnaths similar in size, or irregular mix of large and small paragnaths in a single band; P-bar paragnaths absent, or present.Dorsal notopodial ligule markedly elongate on posterior chaetigers; markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present, or absent. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform, or flattened. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present; homogomph falcigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent; homogomph spinigers present, or absent; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: homogomph spinigers absent; heterogomph falcigers present; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Pseudonereis species are characterised by presence of both P-bars and comb-like rows of paragnaths in Areas II-IV .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present, or absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 3; not markedly elongate on posterior chaetigers ; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notochaetae: homogomph spinigers present; homogomph falcigers present (on posterior chaetigers). Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present; posterior chaetigers heterogomph falcigers with short blades present.Anal cirri form cirriform or conical.Rullierinereis is a genus with similarities to Nicon and Typhlonereis but differing in having notopodial homogomph falcigers . alcigers . FifteenTaxon classificationAnimaliaPhyllodocidaNereididaeHartmann-Schröder, 198571B0A9D9-6CCE-55CB-A33B-8A5C0828603ACeratonereis (Simplisetia) Hartmann-Schröder, 1985.Nereis (Ceratonereis) aequisetis Augener, 1913.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324869.Neurochaetae dorsal fascicle simple chaetae  present; palpophore barrel-shaped, approximately equal width from base to palpostyle ; maxillary ring paragnaths present .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove .Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present, or absent; II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers (rarely markedly reduced on posterior chaetigers). Prechaetal notopodial lobe present, or absent; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process present, or absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe absent, or present; projecting beyond end of the acicular ligule; restricted to anterior chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule, or short, up to half length of acicular neuropodial ligule.S.lizardensis); homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; simple chaetae  present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers present (only in Simplisetia sp. from Phuket), or absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades present, or absent; posterior chaetigers heterogomph falcigers with short blades present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers present, or absent . Dorsal notopodial ligule commences chaetiger 4; dorsal notopodial ligule not markedly elongate on posterior chaetigers; notochaetae homogomph falcigers absent (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle .Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 4; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; present on all chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; present throughout all chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade tapering, with straight margin.Anal cirri form cirriform or conical.Dorsal cirrophores of chaetigers 5–7 of epitokes modified into spherical globular structures. Natatory epitokal modifications in males commence chaetiger 22. Females without natatory modifications.Sinonereis Wu & Sun, 1979 is a monotypic genus originally based on a single epitokous specimen. An emended description including atokous characters was provided by Taxon classificationAnimaliaPhyllodocidaNereididaeGibbs, 1971B069DACD-C9CC-5050-B536-4D41B71D7E34Solomononereismarauensis Gibbs, 1971.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324870.Area II rod-like paragnaths present; prostomium anterior margin indented . Notochaetae homogomph falcigers present; dorsal notopodial ligule markedly reduced on posterior chaetigers (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented. Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present; II conical paragnaths absent; II rod-like paragnaths present; III conical paragnaths absent; III rod-like paragnaths present; IV paragnaths present; IV conical paragnaths absent; IV rod-like paragnaths present. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers absent; sesquigomph spinigers present; homogomph falcigers present; homogomph falcigers with multidentate blade with 2 or more small lateral teeth, first and subsequent lateral teeth much smaller than terminal tooth present; sesquigomph falcigers present, or absent. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers absent; sesquigomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers present; blades serrated. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers absent.Anal cirri form cirriform or conical.Solomononereis is a genus of Nereididae sharing some similarities to members of the larger genus Ceratonereis. Solomononereis, however, can be distinguished by the presence of rod-like paragnaths on the maxillary ring. Solomononereis contains two species, both occurring in the tropical Indo-Pacific to a depth of ~ 30 m. Taxon classificationAnimaliaPhyllodocidaNereididaeWesenberg-Lund, 1958974DE7F1-99C0-5F83-8A37-6CE966A79210Stenoninereismartini Wesenberg-Lund, 1958.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324872.Dorsal cirrus arising from basal cirrophore; ventral neuropodial ligule of anterior chaetigers absent; palpophore surface with a single transverse groove  . Oral ring papillae absent; maxillary ring paragnaths absent; palpostyles subconical (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented; longitudinal groove absent. Tentacular belt equal to or less than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 3; markedly reduced on posterior chaetigers. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; arising from basal cirrophore; cirrophore of dorsal cirrus much longer than ventral notopodial ligule (and ciliated); cirrophore of dorsal cirrus cylindrical throughout.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe present; not projecting beyond end of the acicular ligule; present throughout all chaetigers; flattened (rounded). Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent.Notoaciculae on chaetigers 1 and 2 present. Notochaetae: homogomph spinigers absent; sesquigomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers absent; sesquigomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade tapering, with straight margin; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent. Neuropodial heterogomph spinigers with blades basally serrate, coarse teeth, larger teeth longer than blade width, 2/3 of the blade edentate and subulate. Neuropodial heterogomph falcigers with very long blades, increasing their length from upper to lower positions in the same fascicle; falcigers with blades smooth.Anal cirri form cirriform or conical.Stenoninereis Wesenberg-Lund, 1958 was described for a single species, S.martini Wesenberg-Lund, 1958. The genus now includes four small species, all occurring in sinkholes in the Caribbean-Mexico-central America region. Species of Stenoninereis can be identified using the key of Taxon classificationAnimaliaPhyllodocidaNereididaePillai, 1961E4A27572-88EA-56FD-8C0A-F206C7991603Tambalagamiafauveli Pillai, 1961.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324873.Transverse dorsal lamellae present; neurochaetae dorsal fascicle sesquigomph spinigers absent . Dorsal cirrus arising from basal cirrophore; tentacular belt greater than length of chaetiger 1; notochaetae sesquigomph spinigers absent (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented. Tentacular belt greater than length of chaetiger 1.Jaws with smooth or slightly crenulate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Transverse dorsal lamellae present.Dorsal notopodial ligule present; commences chaetiger 1. Prechaetal notopodial lobe present. Dorsal cirrus arising from basal cirrophore; cirrophore of dorsal cirrus enlarged and vascularised; cirrophore of dorsal cirrus cylindrical throughout.Ventral neuropodial ligule of anterior chaetigers present. Accessory ventral cirrus present.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers absent.Tambalagamia Pillai, 1961 is similar to Ceratocephale and, especially to Gymnonereis, with double ventral cirri being shared characters. Tambalagamia to be a junior synonym of Gymnonereis. We follow Tambalagamia as separate pending phylogenetic analysis with better taxon sampling of both genera. Tambalagamia currently includes three species which can be identified using the tabular comparison of Taxon classificationAnimaliaPhyllodocidaNereididaeFauvel, 1911D2A469FC-05F5-5D2A-A397-E5D6C969B09DTylonereisbogoyawlenskyi Fauvel, 1911.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324874.Dorsal notopodial ligule markedly broader on posterior chaetigers; prostomium anterior margin indented . Maxillary ring of pharynx with papillae present; dorsal notopodial ligule markedly elongate on posterior chaetigers (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented.Jaws with smooth or slightly crenulate cutting edge.Maxillary ring of pharynx with papillae present; in tufts. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI one papillae present; VII-VIII papillae present (in a single row). Oral ring paragnaths absent. Maxillary ring papillae absent on Areas I and II, with double rows on Areas III and IV.Dorsal notopodial ligule present; commences chaetiger 3; markedly elongate on posterior chaetigers; markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule. The neuropodial acicular ligule has three or four distinct lobes; homology of these is unclear, therefore these structures are not scored in this description.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers absent.Tylonereis is one of several genera of Nereididae from tropical estuaries which have papillae on both maxillary and oral rings of the pharynx. The genus contains three species, all known from coastal lagoons and lakes of the tropical Indo-Pacific. Taxon classificationAnimaliaPhyllodocidaNereididaeGrube, 18668F549577-311C-549F-8E5C-EC4B8603F712Nereisheterocheta Quatrefages, 1866.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=324876.Dorsal cirrus terminally attached throughout, so that dorsal notopodial ligule has appearance of a cirrophore for the dorsal cirrus . Acicular notopodial ligule reduced, much shorter than neuropodial acicular ligule; maxillary ring of pharynx with papillae present (secondary diagnosis).Palpophore barrel-shaped, approximately equal width from base to palpostyle . Prostomium anterior margin indented. Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae present. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule absent. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Acicular notopodial ligule reduced, much shorter than neuropodial acicular ligule. Dorsal cirrus length ~ 5× acicular notopodial ligule at chaetigers 10–20; not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; terminally attached throughout, so that dorsal notopodial ligule has appearance of a cirrophore for the dorsal cirrus.Ventral neuropodial ligule of anterior chaetigers absent. Ventral neuropodial ligule on posterior chaetigers absent. The single notopodial ligule  and the nearby north-east Pacific Ocean . Dorsal notopodial ligule commences chaetiger 5; dorsal notopodial ligule not markedly elongate on posterior chaetigers (secondary diagnosis).Tentacular belt greater than length of chaetiger 1. Tentacular cirri extend to chaetiger 2 (longest cirrus).Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 5; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; markedly reduced on posterior chaetigers. Prechaetal notopodial lobe absent. Notopodial acicular process absent. Dorsal cirrus length ~ 1× acicular notopodial ligule at chaetigers 10–20; sub-terminally attached to dorsal margin of dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe absent. Neuropodial postchaetal lobe absent. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae of chaetigers 3 and 4 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers absent; on posterior chaetigers absent. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades absent; posterior chaetigers heterogomph falcigers with extra-long blades present; posterior chaetigers heterogomph falcigers with short blades absent.Typhlonereis is known from a single species represented by six specimens from 2222 m in the far North-east Atlantic Ocean . Notochaetae sesquigomph falcigers present; prostomium anterior margin entire (secondary diagnosis).Antennae present . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area II conical paragnaths present; III conical paragnaths present; III rod-like paragnaths absent; IV paragnaths present; IV conical paragnaths present; IV rod-like paragnaths absent. Oral ring papillae absent. Oral ring paragnaths absent.Dorsal notopodial ligule markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial prechaetal lobe present; extending beyond postchaetal lobe (at least in anterior chaetigers). Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; flattened. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers short, up to half length of acicular neuropodial ligule.Notochaetae: homogomph spinigers present; sesquigomph falcigers present; blade distally bifid. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; heterogomph falcigers blade terminally bifid.Unanereis Day, 1962 was described from a single specimen found in the tube of a species of Terebellidae. A second species, U.zghali Ben Amor, 1980, from a vertical rocky substrate including dendrophyllid coral Astroidescalycularis and algae Corallinamediterranea but without an obvious host, has been described from the Mediterranean .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Palpophore surface with a single transverse groove . Tentacular belt equal to or less than length of chaetiger 1, or greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths absent. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae absent; VI papillae present; VII-VIII papillae present. Oral ring paragnaths absent.Dorsal notopodial ligule present; commences chaetiger 3; not markedly elongate on posterior chaetigers; not markedly broader on posterior chaetigers; not markedly reduced on posterior chaetigers. Prechaetal notopodial lobe present; smaller than dorsal notopodial ligule on anterior chaetigers, usually reduced or absent posteriorly; restricted to a limited number of anterior chaetigers. Notopodial acicular process absent. Dorsal cirrus not sub-terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached to dorsal notopodial ligule on posterior chaetigers; not terminally attached throughout all chaetigers.Neuropodial postchaetal lobe present; projecting beyond end of the acicular ligule; present throughout all chaetigers; digitiform. Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers similar to length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle: heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present; blades serrated; blades with teeth only slightly longer proximally than distally. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; anterior chaetigers heterogomph falcigers with long blades absent; anterior chaetigers heterogomph falcigers with extra-long blades present; anterior chaetigers heterogomph falcigers with short blades absent; posterior chaetigers heterogomph falcigers with long blades present, or absent; posterior chaetigers heterogomph falcigers with extra-long blades absent; posterior chaetigers heterogomph falcigers with short blades present, or absent; heterogomph falcigers blade lacking distinct tendon on terminal tooth.Anal cirri form cirriform or conical.Websterinereis is similar to Rullierinereis in having the anterior margin of prostomium entire, the maxillary ring bare and papillae on the oral ring; Websterinereis differs from Rullierinereis in lacking notopodial homogomph falcigers. There are five species of Websterinereis which are known from the Atlantic, Indian, and Pacific Oceans, mostly from shallow water (less than ~ 130 m) except for W.glauca, which is recorded to a maximum depth of 3310 m. The genus was revised by Taxon classificationAnimaliaPhyllodocidaNereididaeKhlebovich, 1996B6C3393C-54F5-5646-8ECF-8E9D5FEEE89DLeonnatessimplex Monro, 1939.https://www.marinespecies.org/polychaeta/aphia.php?p=taxdetails&id=1039985.Oral ring papillae present; maxillary ring paragnaths present; ventral neuropodial ligule on posterior chaetigers short, up to half length of acicular neuropodial ligule .Palpophore barrel-shaped, approximately equal width from base to palpostyle . Tentacular belt greater than length of chaetiger 1.Jaws with dentate cutting edge.Maxillary ring of pharynx with papillae absent. Maxillary ring paragnaths present. Area I conical paragnaths present; II conical paragnaths present; III conical paragnaths present; III conical paragnaths isolated lateral groups absent; IV paragnaths present; IV conical paragnaths present. Oral ring papillae present. Oral ring papillae arrangement solitary. Area V papillae present; VI papillae present; VII-VIII papillae present; VII-VIII papillae arranged in a double row. Oral ring paragnaths absent.Dorsal notopodial ligule not markedly reduced on posterior chaetigers.Ventral neuropodial ligule of anterior chaetigers present. Ventral neuropodial ligule of anterior chaetigers approx. as long as acicular neuropodial ligule. Ventral neuropodial ligule on posterior chaetigers present. Ventral neuropodial ligule on posterior chaetigers short, up to half length of acicular neuropodial ligule.Notoaciculae on chaetigers 1 and 2 absent. Notochaetae: homogomph spinigers present. Neurochaetae dorsal fascicle heterogomph spinigers absent; homogomph spinigers present; heterogomph falcigers in anterior chaetigers present; on posterior chaetigers present. Neurochaetae ventral fascicle: heterogomph spinigers present; homogomph spinigers absent; heterogomph falcigers present; falcigers blade tapering, with straight margin.Wuinereis was established by Leonnates. The two genera  are similar in having only paragnaths on the maxillary ring and only papillae on the oral ring. Wuinereis can be separated by chaetal and parapodial characters as per the diagnosis given here. The sole species, W.simplex  is known only from Aldabra Atoll in the Indian Ocean.