oligobuninae is an extinct subfamily of the family mustelidae .

the subfamily was described by j. a. baskin in 1998 ; of the genera that he assigned to this clade , eight are recognized today - brachypsalis , megalictis , oligobunis , potamotherium , promartes , zodiolestes , floridictis and parabrachypsalis - representing fifteen separate species .

oligobuninae

oligobuninae <EOT> oligobuninae is an extinct subfamily of the family mustelidae known from miocene deposits in north america .

citation : valenciano a , baskin ja , abella j , pérez - ramos a , álvarez - sierra má , morales j , et al . ( 2016 ) megalictis , the bone - crushing giant mustelid ( carnivora , mustelidae , oligobuninae ) from the early miocene of north america . plos one 11 ( 4 ) : e0152430 . urltoken

the new specimens of megalictis ferox described here ( f : am 54079 , f : am 25430 and amnh 54076 ) give us a broader understanding of the morphology of m . ferox and lead us to conclude that the holotypes of both m . ferox ( amnh 12880 ) and aelurocyon brevifacies ( cm 1590 ) are conspecific and thus the latter should be subsumed into m . ferox . we argue that there are 3 species ascribed to megalictis : m . ferox , m . frazieri and m . simplicidens . however , the fourth potential congener , “m” . petersoni , might be best ascribed to a different genus . our cladistic analysis suggests that m . ferox is the sister taxon of the clade composed by m . simplicidens — m . frazieri . our phylogenetic hypothesis supports the subfamily oligobuninae as being a stem mustelid .

megalictis ferox matthew , 1907 [ 1 ] is a giant mustelid of the subfamily oligobuninae and belongs to the paraphyletic group of “paleomustelids” [ 2 ] . it lived in the early miocene during the late arikareean ar4 north american land mammal age 22 . 7–18 . 5 mya [ 3 , 4 ] of the central great plains of united states in the states of nebraska , south dakota , and wyoming [ 1 , 5 – 7 ] . the ar4 lithostratigraphic units containing giant oligobunines have been revised . hunt [ 8 ] named the anderson ranch formation for the terminal formation of the arikaree group in nebraska and wyoming formerly referred to as the upper harrison beds of peterson [ 5 , 9 ] and the lower marsland formation of schultz [ 10 ] . the black bear formation replaces the upper rosebud formation of south dakota [ 11 ] .

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full reference : j . a . baskin . 1998 . mustelidae . evolution of tertiary mammals of north america 152 - 173

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copyright : © 2016 valenciano et al . this is an open access article distributed under the terms of the creative commons attribution license , which permits unrestricted use , distribution , and reproduction in any medium , provided the original author and source are credited .

data availability : all relevant data are within the paper and its supporting information files .

funding : a . v . has received funding from the european union’s seventh framework programme ( fp7 / 2007 - 2013 ) under grant agreement n° 226506 ( synthesys ; se - taf - 3637 ) , the usc school of medicine ( columbia , south carolina , usa ) , the amnh ( collection study grant program 2014 ) and the international travel grant 2015 from the vertebrate paleontology department of flmnh from uf . a . v . is researcher in formation in the csic program jae - pre _ cp2011 ( csic program " junta para la ampliación de estudios " ) , co - funded by the european social fund . a . p . r . is a pre - doctoral fpi fellowship ( bes - 2013 - 065469 ) of the project cgl2012 - 37866 . this study was also supported by the spanish ministerio de economía y competitividad ( research project cgl2015 - 68333 , cgl2011 - 28877 and cgl2011 - 28681 ) , the research group bsch - ucm 910607 and university of south carolina school of medicine ( columbia , south carolina , usa ) .

abbreviations : acm , amherst college beneski museum of natural history , massachusetts , usa ; ahr , comparative anatomy research collection , university of south carolina school of medicine , columbia , usa ; amnh , american museum of natural history , division of paleontology and division of mammalogy , new york , usa ; cm , carnegie museum of natural history , pittsburgh , usa ; f : am , collection housed in the frick collection of the division of paleontology , amnh , new york , usa ; lgput , laboratory of geology and palaeontology , university of thessaloniki , greece ; mncn , museo nacional de ciencias naturales madrid , spain ; mncncomp , comparative anatomy research collection of paleobiology department of museo nacional de ciencias naturales madrid , spain ; nrm , naturhistoriska rikmuseet , stockholm , sweden ; pin , palaeontological institute , russian academy of sciences , moscow , russia ; sam - pql , iziko south african museum , cape town south african museum , south africa ; tmm , texas memorial museum at the vertebrate paleontology laboratory , the jackson school of geosciences , university of texas , austin , usa ; uf , vertebrate paleontology collection of the florida museum of natural history ( flmnh ) , university of florida , gainesville , usa ; unsm , university of nebraska state museum , lincoln , nebraska , usa ; usnm , united states national museum of natural history , smithsonian institution , washington , d . c . , usa

megalictis ferox [ 1 ] was described from the black bear formation , stanley county , south dakota , usa . a second giant oligobunine , aelurocyon brevifacies peterson , 1907 [ 5 ] , was described from the niobrara canyon local fauna , anderson ranch formation in sioux county , nebraska , usa . hunt and skolnick [ 7 ] established that the actual publication date for a . brevifacies was one week after matthew described m . ferox in 1907 , not in 1906 as indicated in the journal . after these initial descriptions , riggs [ 6 ] described new cranial and postcranial material of both taxa . hunt and skolnick [ 7 ] synonymized megalictis ferox , aelurocyon brevifacies , and the large oligobunine mustelid paroligobunis simplicidens ( peterson , 1907 ) [ 5 ] .

here , we describe an important unpublished sample of craniomandibular remains of megalictis ferox ( f : am 25430 , f : am 54079 , and amnh 54076 ) , housed at the american museum of natural history ( new york , usa ) . although f : am 25430 and f : am 54079 were found in the late 1930s and have been used to obtain metric , morpho - functional and phylogenetic data ( e . g . , [ 2 , 7 , 12 – 16 ] ) , they have never been fully described . therefore , the main objective of the present paper is to describe these unpublished skulls and mandibles , and provide new data on the taxonomy and systematics of the genus in order to shed new light on the paleobiology of megalictis .

dental nomenclature follows ginsburg [ 17 ] and smith and dodson [ 18 ] . anatomical descriptions are based primarily on scapino [ 19 ] , turnbull [ 20 ] , barone [ 21 , 22 ] , waibl et al . [ 23 ] , evans and de lahunta [ 24 , 25 ] , and hartstone - rose et al . [ 26 ] . the terminology conforms to the standard of the nomina anatomica veterinaria [ 23 ] with the exception of the masseter and temporalis muscle complexes for which we follow hartstone - rose et al . [ 26 ] . the megalictis material ( figs 1 – 4 ) has been compared to all the other material of megalictis and paroligobunis on the basis of published descriptions , figures , measurements and photographs . we have re - measured the dentition of amnh 12880 and 22632 ( cast of cm 1590 ) measured initially by matthew [ 1 ] and peterson [ 5 ] and completed the measures of paroligobunis petersoni loomis , 1932 [ 27 ] using a cast tmm 40966–1 . measurements were made using mitutoyo absolute digital calipers to the nearest 0 . 1 mm ( tables 1 and 2 ) .

a lateral view ; b rostral view ; c dorsal view ; d caudal view ; e ventral view . scale bar equals 5 cm .

a right mandible lateral view ; b occlusal view ; c left mandible lingual view of lower dentition . scale bar equals 5 cm .

a1–4 cranium f : am 54079 , lateral view ( a1 ) , dorsal view ( a2 ) , ventral view ( a3 ) , and caudal view ( a4 ) ; b1–3 right hemimandible f : am 54079 , lateral view ( b1 ) , medial view ( b2 ) , and occlusal view ( b3 ) ; c1–3 left hemimandible f : am 54079 lateral view ( c1 ) , medial view ( c2 ) , and oclussal view ( c3 ) ; d1–3 right hemimandible of amnh 54076 , lateral view ( d1 ) , medial view ( d2 ) , and occlusal view ( d3 ) . scale bar equals 5 cm .

a , and b megalictis ferox holotype amnh 12880 , lateral view ( a ) , ventral view ( b ) ; c , and d megalictis ferox cm 1590 ( genotype of aelurocyon brevifacies ) , lateral view ( c ) , ventral view ( d ) ; megalictis ferox f : am 25430 lateral view ( e ) , ventral view ( f ) ; g , and h megalictis ferox f : am 54079 lateral view ( g ) , ventral view ( h ) . scale bar equals 5 cm . c and d courtesy of the carnegie museum of natural history .

f : am 25430 ( figs 1 and 2 , s1 video ) : relatively complete skull with i1 - 3 , c , p1 - 4 and m1 - 2 , missing only its left zygomatic arch , a broken frontal area plus a portion of the right parietal region missing and filled with plaster , a hole in its right parietal bone , and a complete mandible with i1 - 3 , c , p1 - 4 and m1 - 2 ; f : am 54079 ( fig 3 , s2 video ) : right side of a partial skull without the premaxilla , with worn c , p2 - m1 and partial mandibles with a nearly complete right one with c - m2 and a broken mandibular symphysis and a left one just with the mandibular corpus preserved and a broken p2 , and a complete both p3 and m1 ; amnh 54076 ( fig 3 ) : partial mandibular corpus with m1 - 2 .

in order to better understand the phylogenetic relationships of the oligobunines megalictis ferox ( amnh 12880 , cm 1590 , f : am 25430 and f : am 54079 ) , m . simplicidens ( = paroligobunis simplicidens ) ( cm 1553 and cm 2389 ) , m . frazieri ( = paroligobunis frazieri ) ( uf 23928 ) , “ m . ” petersoni ( = paroligobunis petersoni ) ( acm 2011 ) , and oligobunis crassivultus ( amnh 6903 ) , we have performed a cladistic analysis ( fig 5 ) including 18 taxa ( m . ferox is represented in the analysis as 4 separate operational taxonomic units ( otu ) ) and 73 equally weighted and unordered craniomandibular characters ( s1 – s3 appendices ) . cladistic analysis was performed using in paup * 4 . 0b10 [ 38 ] . the analysis was rooted using c . lupus as the outgroup .

searches were performed using the branch and bound and a bootstrap analysis through 1000 replicates to test the clade support in the analysis . the outgroup was c . lupus . strict consensus tree of 6 trees ( length 194 steps , consistency index ( ci ) = 0 . 41 , retention index ( ri ) = 0 . 65 ) for knowing the relationships between the different specimens of megalictis ferox , megalictis simplicidens , megalictis frazieri , “ megalictis ” petersoni , oligobunis crassivultus , and a sample of extant musteloids and a canid . numbers below nodes are bremer indices , and numbers above nodes are bootstrap support percentages ( only shown when ≥ 50 ) . character / taxa matrix is detailed in the s1 – s3 appendices . silhouette of megalictis ferox based on hunt and skolnick [ 7 ] , silhouette of megalictis simplicidens , megalictis frazieri , “ megalictis ” petersoni and oligobunis crassivultus based on megalictis ferox but rescaled according the size of the dentition .

virtual models of the mandibles and skulls of megalictis ferox ( f : am 25430 , f : am 54079 , amnh 12880 and amnh 22632 ) as well as megalictis frazieri uf 23928 and megalictis simplicidens ( cast of cm 1553 ) were derived by means of a 3d nextengine hd laser surface scanner ( s1 – s6 videos ) .

diagnosis : large to giant size mustelid ; robust mandible with a high , wide and distally curved ascending ramus ; deep masseteric fossa with a stout crest that extends from the dorsal border of the coronoid process to below the m2 ; robust dentition ; p1 present ; p2–4 with distal cingula high - crowned ; p4 relatively enlarged with mesial and distal accessory cuspids ; m1 trigonid widened , with a strong lingual concavity between the paraconid and protoconid ; m1 metaconid reduced to absent , present in the older and smaller forms and absent in the giant forms , m1 talonid low and narrow with a short , trenchant and labially located hypoconid ; and m2 with reduced metaconid .

type species : megalictis ferox matthew , 1907 p1 . ii , fig . 1 [ 1 ]

included species : megalictis simplicidens ( = paroligobunis simplicidens ) ( peterson , 1907 ) [ 5 ] and megalictis frazieri ( = paroligobunis frazieri ) ( frailey , 1978 ) [ 28 ] .

synonyms : senior subjective synonym [ 7 ] of aelurocyon brevifacies peterson , 1907 , p . 68 [ 5 ] , “upper harrison formation” , sioux county , nebraska and paroligobunis peterson , 1910 [ 29 ] . hunt and skolnick [ 7 ] synonymized megalictis , aelurocyon , and paroligobunis simplicidens into a single , sexually - dimorphic chronospecies m . ferox . this hypothesis has been generally accepted ( e . g . , [ 3 , 13 , 42 ] ) .

megalictis ferox , hunt and skolnick , 1996 ( pars ) . [ 7 ]

holotype : amnh 12880 , a partial reconstructed skull ( fig 4 , s3 video ) with right p4 , m1 - 2 , a fragmented right mandible with almost complete coronoid process , m1 trigonid and m2 , and very few postcranial remains figured by matthew , 1907 , p . 196 , fig . 10–13 , 15 [ 1 ] .

type locality : rosebud 22 , porcupine butte , black bear formation , stanley county , south dakota .

other localities : rosebud 5 , porcupine butte , stanley county , south dakota , usa ( amnh 12881 ) ; niobrara canyon local fauna , sioux county , nebraska , usa ( cm 1590 ) , “high daemonelix beds” , niobrara canyon local fauna , sioux county , nebraska , usa ( f : am 25430 ) ; j - m district , south of lusk , goshen county , wyoming , usa [ 6 ] ; “high brown sand” , 16 mile district , goshen county , wyoming , usa ( f : am 54079 ) ; 8 north of lusk , goshen county , wyoming , usa ( f : am 54076 ) .

age : upper part of the anderson ranch formation and its equivalents , south dakota , nebraska , and wyoming , late late arikareean ( ar4 ) , 22 . 7–18 . 5 mya [ 4 ] early miocene .

diagnosis : baskin [ 2 ] diagnosed of aelurocyon brevifacies ( which he considered the senior subjective synonym of megalictis ferox because of the presumed earlier publication date at the time he submitted the chapter ) . new or revised characters follow . megalictis ferox is the largest of the oligobunines ; coronoid process high and caudally curved ; enlarged masseteric fossa with a robust crest extending from the dorsal border of the coronoid process to below the m2 ; laterocaudal area of the ventral edge of the mandibular corpus laterally projected ; p2 with distal accessory cusp ; robust p3 ; robust p4 with strong parastyle and protocone ; p4 carnassial notch present ; m1 with enlarged stylar area ; m2 with paracone and protocone ; p2–4 with high - crowned distal cingula ; p3 with mesial and distal accessory cuspid ; p4 relatively enlarged with presence of mesial accessory cuspid and stout distal accessory cuspid ; m1 trigonid widened ; m1 with strong lingual concavity between paraconid and protoconid ; m1 protoconid higher than paraconid ; m1 hypoconid short , trenchant and buccally located ; m1 with a lingual cingulum in the entoconid position ; m2 reduced with metaconid .

differential diagnosis : megalictis ferox differs from m . simplicidens , m . frazieri , “m . ” petersoni and oligobunis crassivultus in its larger size , m1 without metaconid and m1 talonid with a closed lingual morphology with a lingual cingulum between the metacristid and entocristid . additionally , it differs from m . simplicidens and m . frazieri in having a higher and more robust mandibular symphysis , a reduced p2 and a more robust p4 and m1 . it further differs from “m . ” petersoni in much larger size and p3–4 with mesial accessory cuspids . it further differs from oligobunis crassivultus in having a more rectangular p2 , smaller m1 than p4 , enlarged m1 stylar area , higher paracone than metacone on the m1 , reduced p2 , p2–3 high - crowned distal cingula , more developed p3 distal accessory cuspid , relatively enlarged p4 , and higher protoconid than paraconid on the m1 .

comments : specimens that can be referred to m . ferox s . s . are from the latest arikareean ( ar4 ) upper part of the anderson ranch formation and its equivalents .

a nearly complete skull with i1 - 3 , c , p1 - 4 and m1 - 2 ( fig 1 , s1 video ) and a complete mandible with i1 - 3 , c , p1 - 4 and m1 - 2 ( fig 2 , s1 video ) . the left zygomatic arch is missing . part of the frontal and a region of the right parietal bones are missing and filled with plaster . there is a subrectangular and anthropogenic hole in its right parietal bone located above the most caudal area of the zygomatic arch .

locality : “high daemonelix beds” , anderson ranch formation , niobrara canyon local fauna , sioux county , nebraska , usa .

skull and upper dentition : the very well preserved skull f : am 25430 ( fig 1 ) has a basicranial length of 189 . 5 mm . it is slightly domed dorsally at the frontal bone , the bullae are broken and the left zygomatic arch is missing . in general terms the skull is high , domed with a short rostrum and high snout ( fig 1a ) . the nasal aperture is large ( fig 1b ) , and the crushed nasal bones are robust . they are crushed in the mid - sagittal plane and anteriorly the left nasal bone is partially above the right one . the reconstructed frontal region is quite domed . the interorbital region is broad . the postorbital processes are absent . the moderately developed infraorbital foramen is rounded and located above the distal accessory cusp of the p3 . the rostral margin of the orbit ends at the level of the distal margin of the p4 paracone . the orbits are large and rounded . the lacrimal foramen is rounded and relatively large . the sagittal crest is moderately developed and extends caudally where it divides into the nuchal crests , forming a y - pattern ( fig 1a , 1c and 1d ) . in lateral view , the outline of the skull is convex in the temporal region and concave between the temporal bone and nuchal crests .

the zygomatic arches are robust , especially caudally near the glenoid cavity . both m . masseter pars superficialis and m . masseter pars profunda have their origin on the ventrolateral side of the zygomatic arch . the frontal processes of the zygomatic arches are triangular and dorsoventrally high .

mandible and lower dentition : the mandible of f : am 25430 is very robust ( fig 2a and 2b ) . it has a total length of 149 . 0 mm . the tooth row is slightly convex and is aligned with the articular process . the mandibular corpus is high and robust . the ventral margin is convex at the level of the m1 . there is single rounded mental foramen under p2 . the ascending ramus is tall and rostrocaudally broad ( fig 2a ) . its tip is distally oriented . the coronoid process is laterally rotated with an angle of ~ 75 degrees , compared to the articular process . there is a robust crest from the dorsal border of the coronoid to beneath the m2 where the tendon of the m . temporalis is attached . this area is especially enlarged and laterally projected around the area of the m2 ( fig 2a and 2b ) . the masseteric fossa is large and deep . its rostral margin lies at the level of talonid of m1 , and ventrolaterally is limited by a strong area where the m . masseter pars superficialis and m . masseter pars profunda insert . the articular process is large and robust . the angular process is robust and shows a medial crest for the muscular attachment of the m . pterygoideus medialis .

the lower dentition ( 3 / 1 / 4 / 2 ) is also preserved in its entirety ( fig 2 ) . the lower incisors are heavily worn . the canine is large , stout and markedly curved distally ( fig 2a and 2b ) . it has a swollen base and is oval in cross - section . the p1 is oval , single - cusped and distally wide ( fig 2b ) . the p2–4 are stout , subrectangular and wider distally . these premolars have strong cingula at their bases , and the distal cingula are high - crowned . the p2 has a single messially - located cuspid . the p3 has a low mesial accessory cuspid and a more developed distal one . the p4 is the largest lower premolar and has more strongly developed mesial and distal accessory cuspids . the m1 is a relatively short and stout tooth ( fig 2 ) . the very robust trigonid occupies almost three fourths of the total length of the tooth , with the greatest width at the base of the protoconid . the paraconid is lower than the protoconid and there is no metaconid . the m1 shows a markedly lingual concavity in the base of the crown between the trigonid cuspids ( fig 2b ) . the stout talonid lacks an entoconid . the hypoconid is low , trenchant and buccally located . there is a smooth cristid from the top of the protoconid to the hypoconid that encloses a deep lingual depression ( fig 2c ) . the m2 is rounded and low ( fig 2b ) . the paraconid is low , and located in the mesial corner . the protoconid is the highest cuspid , located buccally in the middle of the tooth . the metaconid is situated over the lingual corner . it is less developed than the protoconid . the hypoconid is low and located in the distal corner . there is a cingulum around the whole tooth .

partial skull with worn c , p2–m1 and partial mandible with worn p1–4 and m1–2 ( fig 3a1–4 , 3b1–3 and 3c1–3 , s2 video ) .

locality : “high brown sand” , 16 mile district , anderson ranch formation , goshen county , wyoming , usa .

skull and upper dentition : the skull f : am 54079 ( fig 3a1–4 ) only preserves its right side . it has a maximum length of 180 . 2 mm . the premaxilla is missing , so the basicranial length is unknown . in general terms , f : am 54079 resembles f : am 25430 ( fig 1 ) . the frontal bone and dorsal area of the parietal bone are absent ( fig 3a2 ) . the zygomatic arches are more robust than those of f : am 25430 , especially in the rostral and the central part of the arches , and the origin of m . masseter pars superficialis and m . masseter pars profunda are also more developed . however , the frontal processes of the zygomatic arches are lower than those of f : am 25430 . the glenoid fossa is stout with a very well developed postglenoid process ( fig 3a3 ) . the complete right auditory bulla is large and swollen . the external auditory meati are rounded . the postglenoid foramen , the rostral foramen lacerum and the foramen ovale are similar to those of f : am 25430 . the mastoid process is also robust and expanded . the right occipital condyle is preserved but the caudodorsal area of the skull is not . the paroccipital process is triangular , stout and caudally oriented ( fig 3a1 and 3a3–4 ) .

c , p2–4 and are preserved . the p1 is missing . they are more worn than are those of f : am 25430 . the c has a large lingual wear facet . the morphology of p2–4 ( fig 3a3 ) is almost identical to that of f : am 25430 . the p3 is more quadrangular than that of f : am 25430 , but the mesiolingual corner of the p3 is missing . the p4 paracone , protocone and metastyle are greatly - worn ( fig 3a3 ) . the m1 ( fig 3a3 ) has the same development of the cusps as that found in f : am 25430 , and shows a very similar morphology as that of amnh 12880 . the m2 and its alveoli are not preserved .

mandible and lower dentition : the right hemimandible ( fig 3b1–3 ) has a fragmented corpus that is missing its symphyseal end but includes a complete ascending ramus with p1–4 and m1–2 . its morphology is almost identical to that of f : am 25430 . the left hemimandible ( fig 3c1–3 ) is missing its ascending ramus but includes a complete mandibular corpus , a complete p1 , a fragmented p2 , a highly worn p3 , a complete m1 and a fragmented m2 . the p1–4 and m1 are almost identical to those of f : am 25430 though there is more substantial occlusal wear in p2–4 and m1 than in f : am 25430 . the m2 is oval and has a more developed metaconid than the m2 of f : am 25430 .

locality : 8 north of lusk , goshen county , anderson ranch formation , wyoming , usa .

mandible and lower dentition : amnh 54076 is a fragmented mandibular corpus missing its symphysis ( fig 3d1–3 ) . it has roots for p2–3 , and complete m1–2 . the mandibular corpus is high and robust . the m1 is identical to those of f : am 54079 and f : am 25430 . it has a stout trigonid , and a low talonid composed of a trenchant hypoconid , lingually located and a lingual depression . the m2 is rounded and low . it has a distinguishable protoconid and metaconid , and a continuous basal cingulum .

hunt and skolnick [ 7 ] did not consider the other two species referred to paroligobunis : the small p . petersoni loomis , 1932 [ 27 ] and p . frazieri frailey , 1978 [ 28 ] . as discussed below , we consider the material referred to both p . simplicidens and p . frazieri to be valid species : megalictis frazieri and m . simplicidens .

the results of the cladistic analysis indicate that the specimens we assign to m . ferox form a monophyletic group ( fig 5 ) . we agree with hunt and skolnick [ 7 ] in that m . ferox and a . brevifacies are the same taxon , and that m . ferox has priority . morphologically , the specimens f : am 54079 , f : am 25430 and amnh 54076 , as well as cm 1590 and amnh 12880 , are practically identical to each other ( figs 1 – 4 ) . f : am 54079 differs from f : am 25430 and cm1590 in having a more robust p3 and a relatively longer m2 . cm 1590 has a reduced lingual expansion of p3 and a stronger parastyle of p4 than f : am 54079 , f : am 25430 and amnh 12880 . the morphology of f : am 25430 is clearly different from the skull of amnh 12880 , and shows that the reconstructed parts of the latter were incorrect , in which the temporal , frontal and a part of the zygomatic arch bones are misinterpreted ( fig 4a and 4b ) . f : am 25430 allows us to complete the knowledge about the morphology of the skull of m . ferox and showing that the holotype of m . ferox ( amnh 12880 ) and the holotype of a . brevifacies ( cm 1590 ) belong to the same species . consequently , f : am 54079 , f : am 25430 and amnh 54076 should be assigned to m . ferox . we agree with hunt and skolnick [ 7 ] that the difference observed in the specimens of m . ferox can be explained by intraspecific variability ( sexual dimorphism and intrapopulational differences ) or small temporal differences .

megalictis ferox ( figs 1 – 4 ) is characterized by several traits : long external auditory meatus ; high and caudally curved coronoid process ; enlarged masseteric fossa with a robust crest from the dorsal border of the coronoid process to just beneath the m2 ; latero - caudal area of the ventral edge of the mandibular corpus is laterally projected , with the ventral edge of the angular process also laterally projected ; i3 is enlarged ; p2 with a distal accessory cusp ; robust p3 ; robust p4 with carnassial notch ; enlarged stylar area of m1 , and a m2 with paracone and protocone differentiated ; p2–4 distal cingula high - crowned ; distal accessory cuspid on p3 ; relatively enlarged p4 with a stout mesial accessory cuspid ; relatively stout m1 with a widened trigonid , a strong lingual concavity between the paraconid and protoconid , no metaconid , protoconid higher than paraconid , with a short , trenchant and buccally located hypoconid and a lingual rim in the entoconid position ; reduced m2 with a metaconid .

all the three species that have been referred to paroligobunis ( fig 6 ) are known from limited material . the genotype of paroligobunis , megalictis simplicidens ( cm 1590 , peterson , 1907 , 1910 ) [ 5 , 29 ] comes from the “agate stock farm” , sioux county nebraska . the exact locality is unknown and it is either from the harrison formation ( ar3 ) or the basal part of the anderson ranch formation [ 7 ] . additional material first referred to p . simplicidens [ 29 ] and later to megalictis ferox [ 7 ] is from quarry 3 , beardog hill , agate fossil beds national monument , from the basal part of the anderson ranch formation . the small “m” . petersoni ( loomis , 1932 ) [ 27 ] is from a locality near van tassel , wyoming , “upper harrison beds” ( = anderson ranch formation ) and p . frazieri frailey , 1978 [ 28 ] is from the sb - 1a local fauna , florida , latest oligocene , early late arikareean ( ar3 ) . hunt ( in tedford et . al , 2004 : p . 205 [ 3 ] ) recognized that “‘ paroligobunis’ frazieri is an earlier form preceding the late arikareean species of megalictis ” .

( a ) megalictis simplicidens , type specimen , cm1553 ( peterson , 1907 ) [ 5 ] , lateral view of the mandible , ( b ) megalictis simplicidens cm 1553 ( peterson , 1907 ) [ 5 ] , medial view , ( c ) megalictis simplicidens cm 2389 ( peterson , 1910 ) [ 29 ] , lateral view of the mandible , ( d ) megalictis simplicidens cm 2389 ( peterson , 1910 ) [ 29 ] , medial view , ( e ) megalictis frazieri ( frailey , 1978 ) [ 28 ] , holotype uf 23928 , lateral view of the mandible , ( f ) megalictis frazieri ( frailey , 1978 ) [ 28 ] , uf 23928 , medial view , ( g ) “ megalictis” petersoni ( loomis , 1932 ) [ 27 ] , holotype acm 2011 , lateral view of the mandible , ( h ) “ megalictis” petersoni ( loomis , 1932 ) [ 27 ] acm 2011 , medial view , ( i ) megalictis simplicidens cm1553 ( peterson , 1907 ) [ 5 ] , occlusal view , ( j ) megalictis simplicidens cm 2389 ( peterson , 1910 ) [ 29 ] , occlusal view , ( k ) megalictis frazieri ( frailey , 1978 ) [ 28 ] , uf 23928 , occlusal view , ( l ) “ megalictis” petersoni ( loomis , 1932 ) [ 27 ] acm 2011 , occlusal view . scale bar equals 5 cm . a - d , i and j courtesy of the carnegie museum of natural history . e - f and k courtesy of the florida museum of natural history . g - h and l , beneski museum of natural history at amherst college , courtesy of the trustees of amherst college .

there are no derived characters uniting the three named species of paroligobunis that are not shared with megalictis ( s2 appendix ) . our phylogenetic analysis ( fig 5 ) shows that these three species are paraphyletic with m . ferox . the larger p . frazieri and p . simplicidens are both referred to megalictis . the differences in morphology and size between the three species of megalictis with respect to “ m . ” petersoni ( fig 6 ) suggest that “ m . ” petersoni could be excluded from the genus megalictis .

megalictis simplicidens and m . frazieri ( fig 6 ) resemble m . ferox in several characters , such as a high , wide and distally curved ascending ramus , and a deep masseteric fossa with a robust crest that extends from the dorsal border of the coronoid process to below the m2 . both taxa have a p1 , the distal cingula of p2–4 are high - crowned , and the p4 is relatively enlarged with mesial and distal accessory cuspids . the m1 trigonid is widened , with a strong lingual concavity between the paraconid and protoconid , a low , and narrow talonid with a short , trenchant and labially located hypoconid , and a reduced m2 with presence of a metaconid . however they differ from m . ferox in having a non - reduced p2 , the presence of a stout m1 metaconid , relatively more slender p4 and m1 , m1 talonid with an open lingual morphology between the metacristid and entocristid , and a lower and more slender mandibular symphysis .

hunt and skolnick [ 7 ] partially described and measured some of the unsm and cm specimens of megalictis from the basal part of the anderson ranch formation at beardog hill that we refer to m . simplicidens . aside from their more primitive morphology ( e . g . , presence of a metaconid on m1 ) , they are smaller than m . ferox from the upper anderson ranch formation . the upper and lower dental measurements indicate a size similar to g . gulo .

megalictis frazieri ( fig 6e , 6f and 6k ) differs from m . simplicidens ( fig 6a–6d , 6i and 6j ) in having a less massive mandible and a more distinctive distal cingulum with a higher crown in p2–4 than m . simplicidens . the c and p2 of m . frazieri are also more robust . the m1 hypoconid is higher and the talonid is relatively larger , slightly basined with a very low internal rim .

“megalictis” petersoni ( fig 6g , 6h and 6l ) differs from m . simplicidens and m . frazieri in the absence of mesial accessory cuspids on p3–4 , a relatively stouter p4 with a shorter mesial part and a relatively more robust m1 with a taller and stouter metaconid .

metrically the new megalictis ferox sample described above ( f : am 54079 , f : am 25430 and amnh 54076 ) together with amnh 12880 and cm 1590 form a single picture of m . ferox with dental biometric variability similar to the largest extant terrestrial mustelids gulo and mellivora ( figs 7 and 8 ) . however , if m . simplicidens is considered as a synonym of m . ferox , this variability exceeds the extant one . such variability is much more pronounced when all the specimens of m . simplicidens , m . frazieri and the small “ m . ” petersoni ( figs 7 and 8 ) are included .

a life appearance ; b , reconstructed skull and mandible ; c , skull and mandible f : am 25430 . artwork by adam hartstone - rose .

the preservation of the of m . ferox specimen f : am 25430 represents by far the most complete and best preserved craniomandibular specimen of any giant mustelids . based on the size of the skull , m . ferox emerges as the largest terrestrial mustelid ever known–even larger than the extinct late miocene giant mustelid ekorus , eomellivora , and plesiogulo [ 13 , 32 , 33 , 35 , 37 , 70 ] . this new material sheds light on a new paleobiological interpretation of megalictis as a hyena - like , bone - crushing mustelid , instead of the cat - like ecomorphotype previously ascribed to the genus .

s1 table . list of the extant specimens of carnivorans used in this paper .

s1 video . video of the cranium and mandible of megalictis ferox f : am 25430 .

s2 video . video of the cranium and mandible of megalictis ferox f : am 54079 .

s3 video . video of the cranium and mandible of the holotype of megalictis ferox amnh - 12880 .

s4 video . video of the cranium and mandible megalictis ferox amnh - 22632 ( cast of cm 1590 ) .

s5 video . video of the mandible of megalictis simplicidens ( cm 1553 ) and megalictis frazieri uf 23928 .

s6 video . video of the reconstructed head of megalictis ferox f : am 25430 .

conceived and designed the experiments : av jm ahr . performed the experiments : av jab jm . analyzed the data : av jab ja maas jm ahr . contributed reagents / materials / analysis tools : av ja apr . wrote the paper : av jab ja maas jm ahr .

matthew wd . a lower miocene fauna from south dakota . bull am mus nat hist . 1907 ; 23 : 169–219 .

baskin ja . mustelidae . in : janis cm , scott km , jacobs ll , editors . evolution of tertiary mammals of north america , volume 1 : terrestrial carnivores , ungulates , and ungulate - like mammals . cambridge : cambridge university press ; 1998 . pp . 152–173 .

tedford rh , albright lb iii , barnosky ad , ferrusquia - villafranca i , hunt rm jr , storer je , et al . mammalian biochronology of the arikareen through hemphillian interval ( late oligocene through early pliocene epochs ) . in : woodburne mo , editor . late cretaceous and cenozoic mammals of north america : biostratigraphy and geochronology . new york : columbia university press ; 2004 . pp . 169–231 .

albright lb iii , woodburne mo , fremd tj , swisher cc iii , macfadden bj , scott gr . revised chronostratigraphy and biostratigraphy of the john day formation ( turtle cove and kimberly members ) , oregon , with implications for updated calibration of the arikareean north american land mammal age . j geol . 2008 ; 116 : 211–237

peterson oa . the miocene beds of western nebraska and eastern wyoming and their vertebrate faunae . ann carnegie mus . 1907 ; 4 : 21–72 .

riggs es . some early miocene carnivores . publ - field mus nat hist , geol ser . 1945 ; 9 : 69–114 .

from the early miocene carnivore dens at agate fossil beds national monument , nebraska : earliest evidence of dimorphism in new world mustelidae ( carnivora , mammalia ) . univ wyoming contrib geol . 1996 ; 31 : 35–48 .

hunt rm jr . new amphicyonid carnivorans ( mammalia , daphoeninae ) from the early miocene of southeastern wyoming . am mu novit . 2002 ; 3385 : 1–41 .

peterson oa . a revision of the entelodontidae . mem carnegie mus . 1909 ; 4 : 41–158 .

schultz c . b . the miocene of western nebraska . am j sci . 1938 ; 35 : 441–444 .

martin j e . the rosebud problem revisited . proc s dak acad sci . 2011 ; 90 : 37–50 .

radinsky lb . evolution of skull shape in carnivores . 3 the origin and early radiation of the modern carnivores families . paleobiology . 1982 ; 8 : 177–195 .

werdelin l . mio - pliocene carnivora from lothagam , kenya . in : leakey mg , harris jm editors . lothagam , the dawn of humanity in eastern africa . new york : columbia university press ; 2003 . pp . 261–328 .

holliday ja , steppan sj . evolution of hypercarnivory : the effect of specialization on morphological and taxonomic diversity . paleobiology . 2004 ; 30 : 108–128 .

( arctoidea , carnivora ) from hsanda gol formation , central mongolia and phylogeny of basal arctoids with comments on zoogeography . am mu novit . 2005 ; 3483 : 1–57 .

finarelli ja . a total evidence phylogeny of the arctoidea ( carnivora : mammalia ) : relationships among basal taxa . j mammal evo . 2008 ; 15 : 231–259 .

ginsburg l . order carnivora . in rössner ge , heissig k editors . the miocene land mammals of europe . friedrich pfeil : münchen ; 1999 . pp . 109–148 .

smith jb , dodson p . a proposal for a standard terminology of anatomical notation and orientation in fossil vertebrate dentitions . j vert paleontol . 2003 ; 23 : 1–12 .

scapino rp . biomechanics of feeding in carnivora . ph . d . theses , university of illinois . 1968

turnbull wd . mammalian masticatory apparatus . fieldiana , geol . 1970 ; 18 : 149–356 .

barone r . anatomie comparée des mammifères domestiques , tome 1 , ostéologie 4th edition . éditions vigot : paris ; 1999 .

barone r . anatomie comparée des mammifères domestiques , tome 2 , antrologie et myologie 4 th edition . éditions vigot : paris ; 2000 .

waibl h , gasse h , hashimoto y , burdas kd , constantinescu gm , saber as , et al . nomina anatomica veterinaria . 5th edition . international committee on veterinary gross anatomical nomenclature . world association of veterinary anatomists , columbia , missouri ; 2005 .

evans he , de lahunta a . miller´s guide to the dissection of the dog 4th edition . w . b . saunders company : philadelphia ; 2010 .

evans he , de lahunta a . miller´s anatomy of the dog 4th edition . w . b . saunders company : philadelphia ; 2013

hartstone - rose a , perry j , morrow cj . bite force estimation and the fiber architecture of felid masticatory muscles . anat rec . 2012 ; 295 : 1336–1351 .

loomis fb . the small carnivores of the miocene . am j sci . 1932 ; 24 : 316–329 .

frailey d . an early miocene ( arikareean ) fauna from north central florida ( the sb - 1a local fauna ) . occas pap mus nat hist univ kansas . 1978 ; 75 : 1–20 .

peterson oa . description of new carnivores from the miocene of western nebraska . ann carnegie mus . 1910 ; 4 : 205–278 .

cope ed . on the genera of felidae and canidae . proc acad nat sci philadelphia . 1879 ; 31 : 168–194 .

ozansoy f . étude des hisements continentaux et des mammifères du cénozoïque de turquie . mém soc géol fr , nouvelle série . 1965 ; 44 : 1–92 .

valenciano a , abella j , sanisidro o , hartstone - rose a , álvarez - sierra ma , morales j . complete description of the skull and mandible of the giant mustelid

ozansoy , 1965 ( mammalia , carnivora , mustelidae ) from batallones ( mn10 ) , late miocene ( madrid , spain ) . j vert paleontol . 2015 ; 35 : 4 , e934570 ,

orlov , a new gigantic extinct mustelid ( a contibution to the morphology of the skull and brain and to the phylogeny of mustelidae ) . acta zoologica . 1948 ; 29 : 63–105 .

viret j . menographie paléontologique de la faune de vertébrés des sables de montpellier . iii carnivora , fissipedie . trav lab géol fac sci . lyon . 1939 ; 37 : 1–26 .

hendey qb . late tertiary mustelidae ( mammalia , carnivora ) from langebaanweg , south africa . ann s afri mus . 1978 ; 76 : 329–357 .

teilhard de chardin p . les mustelidés de chine . inst géol peking . 1945 ; 12 : 1–56 .

koufos gd . the late miocene vertebrate locality of perivolaki , thessaly , greece . 4 . carnivora palaeontographica abt a . 2006 ; 276 : 39–74 .

swofford dl . paup * : phylogenetic analysis using parsimony ( * and other methods ) . version 4 . sinauer associates , sunderland , massachusetts ; 2002 .

bowdich te . an analysis of the natural classifications of mammalia , for the use of students and travellers . j . smith , paris ; 1821 .

n . g . n . sp . , ein altertumlicher creodonte aus dem oberoligozan siebenburgens . földtani közlöny . 1943 ; 52 : 10–195 .

fisher g . adversaria zoologica . mém soc imp naturalistes de moscou . 1817 ; 5 : 368–428 .

peigné s , chaimanee y , yamee c , srisuk p , marandat b , jaeger jj . a new member of the mustelida ( mammalia : carnivora ) from the paleogene of southern asia . j vert paleontol . 2006 ; 26 : 788–793 .

cope ed . on two new species of mustelidae from the loup fork miocene of nebraska . amer naturalist . 1890 ; 24 : 950–952 .

riggs es . preliminary description of two lower miocene carnivores . field mus nat hist , geol ser . 1942 ; 7 : 59–62 .

geoffroy saint - hilaire e . palaeontographie . considérations sur des ossemens fossils la plupart inconnus , trouvés et observes dans les bassins de l´auvergne . rev encycl . 1833 ; 59 : 76–95 .

pomel a . mémoire pour server à la géologie paléontologique des terrains tertiaries du department de l´allier . bull soc géol fr ( 2 ) . 1846 ; 3 : 353–373 .

wolsan m . fossil - based minimin divergence dates for the major clades of musteloid carnivorans . in : abstract of plenary , symposium , poster and oral papers presented at ninth international mammalogical congress ( imc 9 ) : roles of mammalogy on coexistence of wild mammals and human , july 31–august 5 , 2005 , sapporo , hokkaido , japan . science council of japan and mammalogical society of japan , tokyo ; 2005 . pp . 372–373 .

finarelli ja , flynn jj . ancestral state reconstruction of body size in the caniformia ( carnivora , mammalia ) : the effects of incorporating data from the fossil record . syst biol . 2006 ; 55 : 301–313 . pmid : 16611601

sato jj , wolsan m , minami s , hosoda t , sinaga mh , hiyama k , et al . deciphering and dating the red panda´s ancestry and early adaptative radiation of musteloidea . mol phylogenet evol . 2009 ; 53 : 907–922 . pmid : 19699810

rybczynski n , dawson mr , tedford rh . a semi - aquatic artic mammalian carnivore from the miocene epoch and origin of pinnipedia . nature . 2009 ; 458 ( 7241 ) : 1021–1024 . pmid : 19396145

willemsen gf . a revision of the pliocene and quaternary lutrinae from europe . scripta geologica . 1992 ; 101 : 1–115 .

tedford rh . relationship of pinnipeds to other carnivores ( mammalia ) . systematic zoology . 1976 ; 25 : 363–374 .

, ( ordo pinipedia , fam . semantoridae fam . nova ) aus den neogen - ablagerungen westsibiriens . tr palcont inst akad nauk sssr . 1933 ; 2 : 165–268 .

] . voprosy geol azii ( an , sssr ) . 1955 ; 2 : 810–814 .

, an oligocene latrine . proc zool soc lond . 1957 ; 129 : 151–244 .

koepfli kp , deere ka , slater gj , begg c , begg k , grassman l , et al . multigene phylogeny of the mustelidae : resolving relationships , tempo and biogeographic history of a mammalian adaptive radiation . bmc biol . 2008 ; 6 : 10 . pmid : 18275614

sato jj , wolsan m , prevosti fj , d´elía g , begg c , begg k , et al . evolutionary and biogeographic history of weasel - like carnivorans ( musteloidea ) . mol phylogenet evol . 2012 ; 63 : 745–757 . pmid : 22410652

li b , wolsan m , wu d , zhang w , xu y , zeng z . mitochondrial genomes reveal the pattern and timing of marten (

) diversification . mol phylogenet evol . 2014 ; 80 : 156–164 . pmid : 25132128

wolsan m , sato jj . effect of data incompleteness on the relative performance of parsimony and bayesian approaches in a supermatrix phylogenetic reconstruction of mustelidae and procyonidae ( carnivora ) . cladistics . 2010 ; 26 : 168–194 .

, sp . nov . ( carnivora : mammalia ) a gigantic otter from the pliocene of dikika , lower awash , ethiopia . j vert paleontol . 2011 ; 31 : 447–453 .

wolsan m , sotnikova m . systematics , evolution , and biogeography of the pliocene stem meline badger

( carnivora : mustelidae ) . zool j linn soc . 2013 ; 167 : 208–226 .

elbroch m . animal skulls : a guide to north american species . stackpole books : mechanicsburg , pa ; 2006

werdelin l . carnivoran ecomorphology : a phylogenetic perspective . in : gittleman jl , editor . carnivore behavior , ecology and evolution . ithaca : cornell university press ; 1996 . pp . 582–624 .

van valkenburgh b . déjà vu : the evolution of feeding morphologies in the carnivora . integr comp biol . 2007 ; 47 : 147–163 . pmid : 21672827

larivière s , jennings ap . family mustelidae ( weasels and relatives ) . in wilson de , mittermeier ra editors . handbook of mammals of the world . 1 . carnivores . lynx editions : barcelona , spain ; 2009 . pp . 564–656 .

hartstone - rose a , wahl s . using radii - of - curvature for the reconstruction of extinct south african carnivoran masticatory behavior . c r palevol . 2008 ; 7 : 629–643 .

hartstone - rose a . reconstructing the diets of extinct south african carnivorans from premolar “intercuspid notch” morphology . j . zool ( lond ) , 2011 ; 285 : 119–127 .

ewer rf . the carnivores . ithaca , new york : cornell university press ; 1998 .

wang x , tedford rh , antón m . the dog family , canidae , and their evolutionary history . columbia university press , new york ; 2008 .

( carnivora : mustelidae ) , from north america . smithson contrib paleobiol . 1981 ; 46 : 1–27 .

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the subfamily was described by j . a . baskin in 1998 ; of the genera that he assigned to this clade , six are recognized today -

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the subfamily was described by j . a . baskin in 1998 , who assigned seven genera to it -

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the dugite / ˈdjuːɡaɪt / ( pseudonaja affinis ) is a species of venomous , potentially lethal , snake native to western australia , a member of the family elapidae .

the local nyungar name for the dugite is dobitj .

dugite

dugite <EOT> dugite - native / package . json at master · desktop / dugite - native · github

perth snake catcher’s joust with fiery 1 . 5m dugite at spearwood factory | perthnow

the dugite is not very aggressive . a member of the brown snake family , the dugite is nowhere near as venomous as its cousin , the eastern brown snake .

dugite snake image by rob ahern - some rights reserved . ( view image details )

workers at the factory spotted a 1 . 5m dugite coiled up outside their kitchen quarters .

snake catcher steve smartt with the fiesty 1 . 5 metre dugite which he later released in bushland .

but the dugite at ms cross ' parents ' home was the first of its kind for the season .

like other brown snakes , dugites are diurnal . the female dugite lays 10 to 20 eggs at a time .

common dugite pseudonaja affinis affinis - notice the broad belly scales on the shed skin . ( photo taken at the west australian reptile park ) an extremely large common dugite pseudonaja affinis affinis - ( photo taken at the west australian reptile park )

the pictures show the dugite wrapping its mouth around the tiger snake ' s body , slowly swallowing the venomous victuals whole .

‘a couple of hours later we saw the culprit by our pond - a 4 ft dugite slithering across the lawn . ’

the fact that the mainland dugite is common in degraded habitats and feeds on house mice suggests that it has a secure future .

kyle releases a rescued brown snake . the dugite is a deadly species of brown snake found in south - western parts of australia .

‘there are several species , the most important medically being the eastern or common brown , the western brown or gwardar and the dugite . ’

dugites are cannibalistic . they eat members of their own species as well as other snakes . an individual dugite can swallow another snake almost as large as itself !

snake handler marcus cosentino , from slithers and sliders who bagged the dugite from mrs cross ' parents ' abode said the area around city beach was notorious for snakes .

well , that question has been settled , sort of , after pictures emerged of a dugite eating a tiger snake near capel in western australia ' s south west .

ms hedzik said she returned to the site later to see if the dugite was still working its way through the tiger snake , but there was no sign of it .

other similar species of brown snake that overlap the dugite’s distribution include the penisular brown snake pseudonaja inframacula , the western brown snake pseudonaja nuchalis and the eastern brown snake pseudonaja textilis .

the 35 - year - old , who is eight months pregnant , said the one metre dugite bolted as soon as it spotted her so she quickly rang a snake handler .

mrs cross , who was aware how deadly a bite from a dugite can be , said at no stage did she fear for the safety of herself or her unborn bub .

they are protected under the australia’s wildlife conservation act 1950 . this means if someone tries to injure or kill a dugite , they can be fined up to aud $ 4000 .

the dugite is a type of brown snake , which is very common around perth and surrounding areas . it is found through the south of western australia through the nullarbor plain and eyre peninsula

in the wild , the dugite eats a variety of vertebrate prey including frogs , lizards , snakes , birds and mammals . however , the two largest groups of prey are lizards and house mice .

the dugite is a highly venomous snake . the adult usually olive green to brown , often with dark spots or flecks . the abdomen may also be dark , unlike that of other brown snakes .

well - known to south - western wa residents , the dugite has made itself at home around urban and semi - rural areas , drawn to the prevalence of its favoured prey – the house mouse .

a heavily pregnant mother - of - one said when she spotted a dugite scurrying across the driveway of her parents ' home , her first thought was to protect her two - year - old daughter .

tiger snake venom activates prothrombin in presence of factor v and calcium , whereas the western brown , brown , dugite , and taipan snakes directly activate prothrombin and may result in very low fibrinogen levels and severe biochemical coagulopathy .

the dugite is a dangerous snake . the venom is neurotoxic although the dugite rarely envenoms when biting people . most people seen in hospital after an attack do not require anti - venom treatment . dugites will avoid people when they can , but will attack if surprised , particularly during mating period . venomous bite symptoms include abdominal pain , breathing and swallowing difficulty , convulsions , hypotension , kidney failure . can be fatal if no anti - venom treatment .

dugites are diurnal , meaning that they aer most active during the day . this is quite common with other brown snakes . in terms of reproduction , a female dugite can lay between 10 to 20 snake eggs at one time .

the dugite is one of nine described species and two subspecies of brownsnake ( genus pseudonaja ) found in australia . the juveniles of all of these are very similar , sharing the dark head - blotch ( or blotches ) . many individuals are adorned with numerous dark crossbands .

the dugite may fall victim to raptors , monitor lizards , feral and domestic cats , and other snakes ( including its own species ) . although vertebrates are probably the main predators of this snake , there is evidence to suggest that spiders occasionally snare and feed on small specimens .

a dugite is an australian species of snake that is highly venomous that can inflict death in simply one bite . it is sometimes refered to as a brown snake and was first described by albert gunther in 1872 . there are 3 sub - species of dugites , and they are :

" the dugite was bigger than the tiger - i thought it would have been the other way around , but he must have moved off , even with that big meal . i think anyone who came across that would have done what i ' d done , anyone would be rapt to see that . "

as mentioned above , the dugite is an extremely venenous snake . in fact , it is one of the most lethal in the world as it causes coagulopathic and precogulant effects ( meaning that the blood will clot and therefore the victim will die ) . despite this , dugites do avoid biting humans but humans are at risk as the numbers of dugite - human encounters rise when they are more active during the mating season which runs during october and november . in fact , the last death that was attributed to this snake was in 1993 , when an elderly male died in spearwood which is one of perth’s southern suburbs .

because of the snake’s size and highly toxic venom the dugite is considered to be very dangerous to humans . its prevalence in residential areas and nervous disposition have helped make it responsible for approximately 70 % of all snake bites reporting to perth hospitals , but thanks to prompt and effective intervention , there has been only one recorded fatality .

dugites are either brown , green , or grey . however , the colors vary between individual snakes . however , the most distinguishable feature of a dugite is the shape of its head . it is quite small compared to the neck , as it grades gradually into the body . they can grow up to 2m ( 6 . 56 feet ) long .

although naturally shy , the dugite is easily agitated when confronted and will raise its forebody upright in a tight s - shape . it hisses loudly before making a fast snappy strike at the offender , usually aiming high . fortunately the fangs are very small and may not effectively penetrate solid shoes or heavy fabric ; however anyone with a suspected bite should seek immediate medical attention .

description : the rottnest island dugite is genetically different from the mainland population and is generally smaller than the mainland version . it is blackish brown all over . it has a long , slim body with a small head . its blackish brown eyes are large and have a golden orange rim . there is also a defined ridge above the eye . its scales are quite large for its body and give it a semi - glossy look .

pseudonaja species live mainly in australia . about 3000 bites occur per year in australia from all species of snakes , 500 of which require antivenin . the dugite brown snake may be found in the southwestern corner of australia , in western australia and along the south australian border . the speckled brown snake can be found from central queensland to the eastern areas of the northern territory . ingram ' s snake may be found around barkly tableland of the northern territory , and the ringed snake may be found in the arid regions of all the mainland states . the western snake may be found throughout australia and the common brown snake in queensland , new south wales , and from victoria to the southeast of south australia .

the brown snake may be found all over australia . it has extremely potent venom , and although the quantity of venom injected is usually small , this snake causes more snakebite deaths in australia than any other . sudden and relatively early deaths have been recorded . its venom causes severe coagulation disturbances , neurotoxicity , and occasionally nephrotoxicity ( by a direct action of the venom ) , but not rhabdomyolysis . the gwardir is also known as the western brown snake , and the dugite is a spotted brown snake found in western australia . all need brown snake antivenom . see also venom supplies brown snake pages , emedicine brown snake guidelines , urltoken , avru brown snake info and treatment , australian reptile park , wikipedia . some more local pics :

the species occupies a wide variety of habitats including coastal dunes , heathlands , shrublands , woodlands and forests . it seems to cope well with heavily degraded habitats such as golf course , industrial parks and open agricultural country ; in fact , it is one of the few reptile species that has probably increased in numbers with the opening up of natural habitats and the introduction of the house mouse . around the perth area , the dugite is one of the most common reptiles found near buildings . in areas of human habitation the snakes take temporary shelter under refuse such as concrete slabs , fibro sheets , roofing tin and the like , but in more “natural” surroundings they will shelter under rocks and in abandoned termite mounds , abandoned stick ant nests , and rabbit and rodent burrows . dugites also use burrows for overwintering .

the number of species increased from 10 , 711 to 10 , 793 , i . e . an increase of 82 species . 66 new species have been described , 9 species have been revalidated from synonymy and 16 subspecies were elevated to full species . . .

over the past 4 months , the number of species increased from 10 , 639 to 10 , 711 .

the number of species has grown from 10 , 544 in the may release to now 10 , 639 ( + 95 species ) .

overall , 212 new taxa have been added or changed their status or name .

the reptile database is a taxonomic database that provides basic information about all living reptile species , such as turtles , snakes , lizards , and crocodiles , as well as tuataras and amphisbaenians , but does not include dinosaurs .

currently there are more than 10 , 000 species and an additional 2 , 700 subspecies . this is making reptiles the largest vertebrate group after fish ( ~ 25 , 000 species ) and birds ( ~ 10 , 000 species ) , and significantly larger than mammals ( ~ 5 , 000 species ) or amphibians ( ~ 6 , 000 species ) .

the reptile database provides taxonomic information for the catalogue of life and the encyclopedia of life . our taxonomic information has also been used by genbank and many other resources and is the only comprehensive reptile database on the web .

the reptile database can be used to find all species within a certain geographic area ( e . g . all snakes of egypt ) . its collection of more than 2 , 500 images allow users to identify a species or at least get an idea how the species or genus may look like . more than 30 , 000 references provide a guide to further information .

this database is maintained by peter uetz ( database content ) and jakob hallermann , zoological museum hamburg ( new species and updates ) .

the three subspecies are fairly similar in general appearance . the body is long and slender in build . scales are relatively large with a semi - glossy appearance . the head is rather small and indistinct from the neck . there is a strong brow ridge over the large eye , which is blackish brown with a golden orange rim surrounding the round pupil . the mouth lining is pink , while the glottis and trachea are black .

mainland subspecies pseudonaja affinis affinis - the overall colour ranges from brown to olive brown to brownish grey , with irregular black / dark grey spotting ( each spot covering half to a whole scale ) . eastern and southern individuals are more heavily spotted ( sometimes becoming totally dark ) . the ventral surface is pale grey to brown with brownish orange or dark grey blotches .

the two island subspecies pseudonaja affinis exilis and p . a . tanneri are generally smaller and usually a uniform blackish brown above .

midbody scales in 19 rows , ventrals 190 - 230 , anal and subcaudal scales divided .

pseudonaja affinis affinis can reach total lengths of 2m ; however the average is probably around 1 . 5m . a specimen kept for some years in the perth zoo reached a total length of 2130mm . the two island subspecies appear to be smaller than the mainland subspecies , with the maximum recorded snout - vent lengths for pseudonaja affinis exilis and p . a . tanneri being 1005mm and 859mm respectively .

pseudonaja affinis affinis – far southwest corner of western australia , extending eastwards into western coastal south australia .

p . a . tanneri - boxer island and figure of eight island in the recherche archipelago ( wa ) .

the snakes are usually most active in the period between early spring and early autumn ( october through april ) and much less active from mid - autumn through late winter ( may through august ) .

they are known to be cannibalistic in the wild , and individuals can swallow snakes almost as large as themselves .

dugites actively search for prey sheltering in holes , crevices , tussock grasses and under surface debris . the snake employs both venom and constriction to subdue its prey .

the species is diurnal . on hot days , activity occurs mainly in the morning and to a lesser extent in the afternoon .

in captivity , adults can darken over the course of a few months . however , the significance of this colour change is obscure .

in the mainland subspecies , males appear to mature at a snout - vent length of about 581mm and females at about 680mm .

in the wild , male combat and mating occurs in late winter - early spring ( september ) , although male combat has been observed in pseudonaja affinis tanneri in mid - spring on boxer island . in the mainland population male combat involves , at least partly , the combatants loosely entwining their bodies . in captivity , mating can occur year around if the temperature is kept warm enough . after mating , captive females are said to eat very large amounts of food . a captive female weighing 309g when mated weighed 580g 27 days later . this represents an 87 . 7 percent gain and implies a daily rate gain of about 10g per day .

wild caught females from the mainland lay their eggs from late spring to mid - summer ( mid - december to end of january ) . the clutch size ranges from 11 to 35 ( average 21 ) for mainland dugites . in the smaller island pseudonaja affinis tanneri , it ranges from 12 to 15 . eggs from mainland dugites have taken between 53 days ( at 30°c ) and 105 days ( at 23°c ) to hatch .

wind the bandage around the bitten arm or leg , starting from the bite .

seek medical attention as soon as possible . first aid guidelines were correct at time of publication however these guidelines change over time . for up to date first aid information consult medical professionals such as st john ' s ambulance .

mirtshin , p . and davis , r . ( 1991 ) “dangerous snakes of australia” , revised edition , ure smith press

wilson , s . and swan , g . ( 2008 ) “a complete guide to reptiles of australia” , reed new holland

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the source is in typescript , but can be consumed by any javascript application .

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as this is under active development , the roadmap is also subject to change . some ideas :

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scarborough mum daile cross was dropping her daughter olivia at her parents ' house in city beach on thursday morning when she noticed something black and skinny on the driveway near a car .

" mum still had olivia in her arms so i yelled at my mum to get her out of there , " she said .

" i panicked a little because i have a phobia of snakes – i would rather have a spider fall on my head .

" i saw the snake heading towards the garage and i thought , ' you are not going in there ' , so i pressed the button for the garage . "

the quick - thinking producer at watoday said she also bellowed at the two painters working at her parent ' s home to keep a look out for the unwelcome reptile .

" i ' m a bit of a mumma bear , so i just wanted to protect olivia , " she said .

" dugites are roaming throughout the area , because it is near a dune system and near bold park , " he said .

" there are strips of bushland all around there so you see them all the way down to scarborough . "

mr cosentino was blunt when asked what would ' ve happened to mr cross if she was bitten .

" if she was bitten she would ' ve obviously been taken to hospital , and i ' m not sure what stress it would ' ve had on the unborn baby , " he said .

" but dugites are dangerous and venomous so essentially a bite could have been fatal . "

mr cosentino said with the warmer weather over the last couple of days , he ' s had a number of call outs for tiger snakes .

" i usually get about 50 call outs for dugites over the summer , but i usually only grab about 20 , because people forget to keep on an eye on them , " he said .

last month a 75 - year - old woman died from a suspected snake bite south of fremantle after the warmest august day in 17 years brought the reptiles out of their torpor . follow watoday on twitter

the rare photos were taken by natalie hedzik , who works at iluka resource ' s mining operations near capel , and said it was a chance encounter .

" i was driving along a track after taking some water samples at a dam we have and just saw this mass in the middle of the road . i got out and had a look and was just absolutely amazed . i ' m really rapt to have seen something so amazing , " she said .

adam firstenberg from perth hills reptile removal said ms hedzik ' s photographs have captured an extremely rare event .

" i certainly haven ' t ever seen it in the wild before . they [ snakes ] will eat reptiles . . . i ' ve seen a snake eat a bobtail lizard before . but they have rear facing fangs to keep food moving backwards , so it ' s going to take a while for the snake to digest another snake . "

australian tiger snakes are widely considered to be among the top 10 most deadly in the world , while dugites are known to use both venom and constriction to subdue their prey .

but mr firstenberg said it ' s unlikely the snakes fought to the death .

" snakes are very opportunistic eaters , so if they need a meal and the opportunity is there they will take it , " he said .

" but this is certainly a very rare occurrence . we keep snakes ourselves and we feed them once a week , so this is a pretty meal to take on . "

if you need more of a snake fix , here ' s a rare sighting of a snakes ' mating ritual in nsw bushland .

the dinosaurs of zoorassic park are coming back but this time they’re bringing some never before seen friends . australian prehistoric megafauna !

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perth zoo works with the community and with partners here and overseas to save wildlife habitats .

this dangerous brown snake is slightly less venomous that its eastern counterparts and much less aggressive .

description : dugites are venomous snakes . they vary in colour from grey to olive to brown on the top of their bodies , with an olive or yellowish belly . black scales can be scattered over the body and the head can be paler or darker than the rest of the body . young dugites have black heads .

diet : dugites are carnivores . before human settlement they mostly ate other reptiles , such as lizards and snakes . since then they have adapted well to eating mice and rats .

in the wild : they may be found sheltering beneath logs or rocks or living in abandoned burrows or hollow logs . when disturbed , dugites are very shy and will often slither away , however , they will defend themselves if cornered .

the main natural predators of dugites are birds of prey and monitor lizards . introduced animals such as cats and dogs also attack dugites .

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a highly venomous snake found in south - western australia , similar to the related brown snakes .

‘other examples resembling the general appearance of dugites from the middleback ranges and environs have been found . ’

‘this includes many populous areas , and dugites are a relatively frequent cause of snakebite in this area . ’

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archaic words have a charm that never fades away , from french sounding to wondrously mysterious ones .

adjectives are used with nouns to make the meaning more specific . if you use the noun‘ bear’ it can mean any animal of that species . as soon as you say‘ a large , brown bear’ you have given two of its . . .

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dugites live in abandoned burrows or hollow logs . they can also be found sheltering underneath rocks or logs . in the summer months , they are often seen sunning themselves on roadsides .

dugites are very shy but will attack if they feel threatened . when it attacks , it lifts its head and front part of its body up into an s - shape . it hisses loudly and then makes a sharp strike . this snake has small fangs but highly toxic venom which is dangerous to humans . these snakes should never be approached and should only be watched from a distance . anyone who may have been bitten by a snake should find medical help immediately .

dugites search for prey in holes , cracks , small caves , grasses and under surface debris . it kills its prey by biting it and injecting venom and by wrapping its body around the animal and squeezing . this wrapping and squeezing is called constriction .

not listed under iucn ( 2016 ) . listed as vulnerable under the wildlife conservation act 1950 . all rottnest island’s fauna is protected under the rottnest island authority act 1987 .

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lays 10 - 20 eggs . hatchlings are 15 - 35 cm in length and can be brown , green or yellowish in colour , but always hatch with at least part of the head black .

map is from atlas of living australia website at urltoken licensed under creative commons attribution 3 . 0 australia license

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cross - env local _ git _ directory = . / git / mocha - t 20000ms - - require ts - node / register test / slow / * . ts test / auth / * . ts

mocha - t 20000ms - - require ts - node / register test / external / * . ts

{ examples , lib , script , test } / * * / * . ts

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- storr et al . ( 2002 ) . snakes of western australia . western australian museum . 309

dangerously venomous . note : even a bite from a ' virtually harmless ' or non - venomous reptile can result in serious complications . play it safe and don ' t get bitten by anything .

note : these are general threats and may not apply to this particular species .

there are many ways you can help our reptiles . here are my top three suggestions :

storr , g . m . ; smith , l . a . ; & johnstone , r . e . ( 2002 ) . snakes of western australia . western australian museum . 309 - search web for this book

note : the links below are automatically generated . some may not take you to useful information .

notes and disclaimer this information may not be complete . while all care is taken to ensure the accuracy of the information in this page , primary sources should always be consulted for definitive information . animals have an endearing habit of disobeying the rules , so the information on this page should be interpreted with a degree of flexibility . the author and site operator accepts no responsibility for any losses or damages incurred through using this web site or the information contained herein . don ' t get bitten by anything ! this page may be cited as : pseudonaja affinis at the australian reptile online database . last updated 2017 - 04 - 22 13 : 20 : 54 . retrieved from urltoken on the 10th of july , 2018 . before citing information contained in arod , please read our citing arod page . copyright notice this page , its content and layout are copyright © 2007 - 2018 stewart macdonald / ug media , unless otherwise stated . all photographs in the australian reptile online database are © the photographer and may not be reproduced in any form without the express written consent of the photographer . no part of the australian reptile online database may be reproduced without written permission from stewart macdonald .

brown snakes are probably the most common cause of significant snakebites in australia . without appropriate antivenom treatment , a significant number of cases may be fatal . main risks are : coagulopathy , acute renal failure , neurotoxic paralysis . target organs : neuromuscular junction , coagulation system , kidneys .

locally : the bite is usually painless , without significant local erythema , bruising or oedema . bite marks may be difficult to see , and vary from a single puncture to multiple punctures or multiple scratches . local secondary infection is unusual . venom may spread to draining lymph nodes with consequent pain and / or tenderness and / or swelling . systemic : headache , nausea , vomiting , abdominal pain , impaired conscious state , occasionally loss of consciousness and convulsions . coagulopathy , rarely with overt bleeding manifestations . progressive neurotoxic paralysis can occur but is unusual . acute renal failure .

monitor coagulation to establish the presence and extent of coagulopathy , and as an index of systemic envenomation . this should be performed at presentation , on development of symptoms or signs of systemic envenomation , regularly thereafter , and 1 - 2 hours after antivenom therapy until sufficient antivenom has been given to reverse coagulopathy . in the absence of a haematology laboratory , whole blood clotting time in a glass test tube is useful . if a laboratory is available , prothrombin ratio , activated partial thromboplastin time , thrombin clotting time , fibrinogen level , and fibrin ( ogen ) breakdown products are most useful . other useful tests are complete blood picture and platelet count , serum electrolytes , creatinine , urea , serum enzymes , especially creatine kinase , urine output and urine myoglobin , and venom detection using csl venom detection kit . best sample is swab from bite site ( sample swab stick in kit ) . if patient has systemic envenomation urine may also be useful sample . blood is not a reliable sample .

venom is produced in paired modified salivary glands , superficially situated beneath the scales , posterior to the eye , and surrounded by muscles , the contraction of which compress the glands , expelling venom anteriorly via venom ducts to the fangs . the paired fangs , situated at the anterior part of the upper jaw , on the maxillary bones . they have an enclosed groove for venom transport , with an exit point near the fang tip . average fang length in adult brown snakes is 2 . 8 mm ( 2 . 0 - 4 . 0 mm ) , and average distance between fangs is 9 mm . average venom yield is 2 - 6 mg , maximum 167 mg ( pseudonaja textilis ) . mean venom injected at first bite ( defensive strike ) is 4 . 5 mg ( 0 . 03 to 9 . 10 mg ) , mean venom left on skin is 0 . 22 mg .

pseudonaja venom is a complex mixture of protein and non - protein components , not all of which have been fully evaluated . ( a ) neurotoxins : both presynaptic ( eg textilotoxin ) and postsynaptic ( pseudonajatoxin a and b ) . ( b ) procoagulants : principally prothrombin converters ( factor xa analogues ) , converting prothrombin to thrombin ( meziothrombin ) . ( c ) nephrotoxins : not conclusively demonstrated experimentally , but strongly suspected on clinical evidence .

3 . 1 . 2 habitat brown snakes occupy a wide variety of habitats from arid dessert , to scrubland , to moister areas . they are not uncommon in association with man ' s activities , such as in paddocks , around rubbish dumps and farm buildings , and under elevated floors of country homesteads . principally diurnal , though active on warm nights .

3 . 1 . 3 distribution brown snakes are restricted to continental australia and a few adjacent islands but not tasmania ( longmore 1986 ) . p . textilis is also reported from papua new guinea . ( cogger 1975 ) . distribution for each species based on museum records are shown in figures .

venom glands ( paired ) situated superficially in posterior part of head , connected by ducts to forward placed ( paired ) fangs . fangs small , may leave classic single or double puncture in man , or a more complicated array of scratches and other punctures , the latter by non - fang teeth ( white 1987a , c ) . classic bite mark in plaster is shown in figure . actual cases illustrated in figures .

3 . 3 . 1 name : pseudonaja venom ; brown snake venom ; bsv components neurotoxins : textilotoxin ( = textilon ) ( coulter et al 1979 , southcott and coulter 1979 , coulter et al 1983 , su et al 1983 ) tyler et al 1987a ) pseudonajatoxin a ( parnett et al 1980 ) pseudonajatoxin b ( tyler et al 1987b ) coagulants : prothrombin converter ( unnamed ) from p . textilis . ( coulter et al 1983 , masci et al 1987 , white et al 1987 ) .

venom is used both in antivenom production and for laboratory research . the neurotoxins in particular may prove valuable in neuromuscular transmission research , and the procoagulants in further elucidating the mechanism of normal human coagulation .

children : when playing in areas were brown snakes are common , either through accidental encounter ( ie stepping on snake ) or while trying to emulate naturalists ( ie trying to catch snake ) . adults : when living in areas where brown snakes are common , and moving around barefoot and without due care , or while putting hands etc into non - reconnoitred potential snake retreats ( ie hollow logs etc ) . farm workers : when working in areas where brown snakes are common . reptile keepers and snake handlers : if due care is not exercised in catching and handling snakes , including venom milking . recreation seekers : camping or walking or playing sport in areas where brown snakes are common . homes : around homes in brown snake prone areas where water is seasonally scarce and free water is available in the garden or home .

brown snakes are widely distributed in most habitats of mainland australia , but are absent form some southern islands and tasmania . while no high risk geographic regions have been identified , it is evident that brown snakes may readily enter metropolitan fringes , and country towns , and are frequently found around country rubbish dumps and under the floors of elevated country homesteads , and around farm buildings .

no data , but unlikely to be hazardous unless there are open wounds in the gastrointestinal tract .

there is no evidence that venom can be absorbed through intact skin . current first - aid advice is to leave venom on skin for later venom identification .

5 . 5 . 1 bites in human envenomation , venom is always inoculated by the snake biting . owing to the size of the fangs , venom is most likely to be inoculated cutaneously or subcutaneously .

experimentally , venom may be administered to test animals via subcutaneous , intramuscular , intravenous , intraperitoneal , and intraventricular ( cns ) routes .

the rate and amount of absorption will depend on the quantity of venom injected , the depth of injection , site of injection including vascularity , the activity of the victim , and the type , efficiency of application and length of application of first aid . clinical evidence from human cases of envenomation suggests that much initial venom movement is via the lymphatic pathways . this is supported by work in monkeys . ( barnes & trueta , 1941 ; sutherland et al 1975 ; sutherland & coulter , 1977 ; sutherland et al 1981a ) direct intravenous injection , unrecorded in man , obviously allows rapid systemic circulation of venom and may result in different effects from normal routes of inoculation , particularly in regard to coagulation .

it appears that much venom is transported from the bite site via the lymphatic system , then concentrating in draining lymph nodes , before ultimately reaching the systemic circulation . however , experience with numerous human cases of brown snake envenomation shows that symptoms and signs of envenomation may occur within 15 - 30 minutes of the bite , especially in children . such early effects ( eg headache , nausea , abdominal pain , collapse ) may be due to either rapidly systemically circulating venom toxins , or systemically circulating autocoids released at the bite site by the action of venom on local tissue . once in the systemic circulation , venom rapidly reaches high concentrations in the kidneys and excreted in the urine . such venom must also exit the circulation , to enter the extravascular space where it binds within the neuromuscular junction ( presynaptically and / or postsynaptically ) and possibly other nerve junction sites ( eg autonomic system , perhaps causing abdominal pain ) . the kinetics of venom distribution , excretion , and detoxification are incompletely understood . neurotoxic paralysis usually takes at least 2 - 4 hours to become clinically detectable . coagulopathy however may become well established within 30 minues of a bite .

little information is available on the metabolism of venom components in man , but most components are fully active in whole venom , requiring no further modification for activity . venom reaches high concentrations in the kidneys and excreted in urine . ( sutherland & coulter , 1977 a , b ) . the fate of specific venom components , particularly neurotoxins and procoagulants , is unclear . it seems likely that these components are progressively detoxified in situ .

7 . 2 . 1 . 1 adults the human lethal dose for brown snake venom is unknown . without antivenom treatment , a few brown snake bites may be fatal ( fairley 1929a ) , but even in the early part of the 20th century , when neither antivenom nor icu facilities were available , only 8 . 6 % of reported brown snake bites were fatal . despite this , brown snakes are still thought to be the most common cause of fatal snakebite in australia . ( hilton 1989 ) .

7 . 2 . 1 . 2 children no data available , but clearly the smaller body mass of a child compared to available venom ensures that children are more likely to receive a lethal dose than adults .

7 . 2 . 2 animal data ld50 subcutaneous injection of dried venom in mice ( broad et al 1979 . ( mg / kg ) pseudonaja textilis 0 . 053 pseudonaja nuchalis 0 . 473 pseudonaja affinis 0 . 660

8 . 1 . 1 . 1 toxicological analyses for venom detection swab from bite site moistened in sterile saline . if systemic envenomation also collect urine ( 5ml in sterile container ) . for venom analysis ( research only using radioimmunoassay ) : 5ml blood ; 5ml urine , frozen . at autopsy collect vitreous humor , lymph nodes draining bite area , excised bite site . ( for other laboratory tests see 10 . 2 . 1 )

8 . 1 . 1 . 2 biomedical analyses for standard tests ( eg . serum / plasma electrolytes , ck , creatinine , urea ) collect venous blood in a container with appropriate anticoagulant as issued by the laboratory ( usually heparin ) .

8 . 1 . 1 . 3 arterial blood gas analysis collect arterial blood by sterile arterial puncture into a container as issued by the laboratory .

8 . 1 . 1 . 4 haematological analyses for whole blood clotting time as a " bedside " test collect 5 - 10 ml of venous blood without anticoagulant ( either in the collection syringe or from a central line or other venous access line that may have anticoagulant ) and place in a glass test tube . carefully observe the time until a clot appears . for standard tests ( eg . coagulation studies , complete blood picture ) collect venous blood in appropriate containers with anticoagulant as issued by the laboratory ensuring that the right amount of blood is used ( for coagulation studies citrate will usually be the anticoagulant , while edta will be used for complete blood pictures ) .

8 . 1 . 2 . 1 toxicological analyses for samples for standard venom detection : short term ( less than 24 hrs ) ordinary fridge is acceptable ( 4°c ) , in sterile container . long term , store frozen ( - 20°c or lower ) . for samples for venom analysis ( research ) store frozen ( - 200°c or lower ) .

8 . 1 . 2 . 2 biomedical analyses for samples for standard tests refer to laboratory . in general keep at 4°c , particularly for samples for coagulation studies .

8 . 2 . 1 . 2 advanced qualitative confirmation test ( s ) as for 8 . 2 . 1 . 1

8 . 2 . 1 . 3 simple quantitative method ( s ) not applicable .

8 . 2 . 1 . 4 advanced quantitative method ( s ) a radioimmune assay has been developed by staff at the commonwealth serum laboratories , melbourne to detect small quantities of many australian snake venoms . it is primarily a research tool , being too time consuming to be practical in determining emergency treatment of snakebite victims . it has proved useful in demonstrating snake venom either at autopsy or after patient recovery .

8 . 2 . 2 . 1 simple qualitative test ( s ) see 8 . 2 . 1 . 1 .

8 . 2 . 2 . 2 advanced qualitative confirmation test ( s ) see 8 . 2 . 1 . 1 .

8 . 2 . 2 . 3 simple quantitative method ( s ) not applicable .

8 . 2 . 2 . 4 advanced quantitative method ( s ) see 8 . 2 . 1 . 4 .

8 . 2 . 2 . 5 other dedicated method ( s ) no data .

8 . 2 . 3 interpretation of toxicological analyses for venom detection as for 8 . 1 . 1 . 1 subsection ( 12 ) : if the test is positive , it will indicate the presence of snake venom and the species / genus of snake and therefore the appropriate monovalent antivenom to neutralize the effects of that venom . if the test sample was a bite site swab , a positive result does not indicate either the presence of systemic envenomation , or the need to administer antivenom . other clinical criteria are required in this situation ( see sections 9 and 10 ) . if the test sample was urine a positive result indicates present or past systemic envenomation and together with other clinical and laboratory criteria may be used to determine the need for antivenom therapy . for venom analysis refer to the laboratory performing the tests .

8 . 3 . 1 . 1 blood , plasma or serum electrolytes : look for imbalance , particularly evidence of dehydration , hyponatraemia ( inappropriate adh syndrome ? ) , hyperkalaemia ( renal damage , rhabdomyolysis ? ) . urea , creatinine : look for evidence of renal function impairment . ck : if high may indicate rhabdomyolysis , usually greater than 1000 u / l .

8 . 3 . 1 . 2 urine output : low output may indicate renal damage or poor fluid input . myoglobin : if present indicates rhabdomyolysis , and may be missed as the red colouration of urine may be mistaken for haematuria ( both may be positive on dip stick testing ) . electrolytes if indicated ( eg . inappropriate adh syndrome )

8 . 3 . 2 arterial blood gas analysis impaired respiratory function is usually secondary to neurotoxic paralysis ; look for evidence of poor oxygenation and its sequelae .

8 . 3 . 5 interpretation of biomedical investigations the interpretation of the above tests should be made in the context of total patient assessment including clinical evidence of pathology such as paralysis , myolysis , coagulopathy and renal damage .

while other investigations are not usually required to make the primary diagnosis of snakebite envenomation , they may be indicated in response to secondary effects of envenomation . if there is either renal failure or severe rhabdomyolysis ( unlikely with brown snake envenoming ) there may be a hyperkalaemia , hence an ecg may be appropriate . if the patient is unconscious , especially in the presence of a severe coagulopathy , then a ct head scan may be appropriate to determine if there is intracranial pathology such as a haemorrhage .

overall interpretation of the results of the above tests will depend on the clinical setting . results should never be interpreted in isolation from an overall clinical assessment . a patient with positive venom detection from either the bite site or urine and a significant coagulopathy clearly is envenomed and will usually require antivenom therapy . a patient with positive venom detection from the bite site only and with no clinical symptoms or signs of envenoming and all other tests negative is not significantly envenomed at that point in time and does not require antivenom therapy . however this situation may change and so careful observation and repeat testing would be indicated . a patient presenting some hours after the bite with positive venom detection from the urine but clinically well and with all other tests either normal or showing a resolved coagulopathy , probably had a minor degree of envenomation , now resolved and will usually not require antivenom therapy . however they should be observed carefully for evidence of relapse .

9 . 1 . 5 parenteral exposure in practical terms , the only likely route of entry , is by s . c . or i . d . injection . early symptoms , usually in the first six hours . local : the wound is often painless , without local erythema , oedema , or ecchymosis ; persistent bleeding from wound , variable ; pain or swelling of draining lymph nodes ( may take 1 - 4 hours to develop ) . systemic : collapse , unconsciousness , convulsions may all occur , especially in children , occasionally as rapidly as 15 minutes after the bite . headache , nausea , vomiting , abdominal pain , and visual disturbance may all occur . early signs of neurotoxic paralysis such as ptosis , diplopia , dysarthria may develop within 1 - 3 hours of the bite , or be delayed for 4 - 12 hours , or may not develop despite other evidence of severe envenomation . coagulopathy may develop within 30 minutes of the bite . delayed symptoms local : local bite site necrosis is not generally seen with brown snake bites but possibly might occur , particularly if first aid left in place more than 4 hours , or if a tourniquet used ( sutherland 1981 , 1983a ; white 1987d ) . systemic : paralysis progressive up to complete paralysis . coagulopathy bleeding from all puncture wounds . renal impairment oliguria or anuria .

9 . 4 . 1 cardiovascular collapse , presumably due to hypotension , is common in the early stages of systemic envenomation , especially in children . the mechanism is uncertain but may be due to release of vasoactive substances by or from the venom . specific cardiac abnormalities due to brown snake envenomation in man are not described , although there has been a suspicion that brown snake venom may cause cardiac anomalies ( sutherland personal communication ) .

9 . 4 . 2 respiratory no primary effects of brown snake venom on the respiratory system in man are reported , with the exception of respiratory muscle paralysis ( see below ) .

9 . 4 . 3 . 1 cns while no direct cns toxins have been reported for brown snake venom , early collapse and convulsions do occur , especially in children . their aetiology remains uncertain .

9 . 4 . 3 . 2 peripheral nervous system see 9 . 4 . 3 . 4

9 . 4 . 3 . 4 skeletal and smooth muscle the effects of brown snake venom at the neuromuscular junction , have been documented experimentally . both presynaptic and postsynaptic neurotoxins present , causing progressive neuromuscular paralysis , up to complete paralysis of all muscles of respiration .