Parasitism by Monogenoidea in Piaractus mesopotamicus (Characiformes, Characidae) cultivated in Paraná River (Brazil).
This study investigated the occurrence, prevalence, mean abundance and mean intensity of monogenoidean parasites in Piaractus mesopotamicus farmed in cages in the reservoir of the Itaipu Hydroelectric Power Station, Paraná River, Brazil. The parasite distribution pattern and the correlation of prevalence and abundance with the total length of hosts were also investigated. Four monogenoidean species were collected: Anacanthorus penilabiatus, A. toledoensis, Mymarothecium ianwhitingtoni and M. viatorum. All the parasites collected in P. mesopotamicus showed the typical aggregated distribution pattern, and the abundance and the prevalence did not shown any correlation with the total length of hosts.
Ecologia da comunidade de metazoários parasitos da Maria-Luiza, Paralonchurus brasiliensis (Osteichthyes: Sciaenidae) do litoral do Estado do Rio de Janeiro, Brasil - DOI: 10.4025/actascibiolsci.v25i2.2009
Ninety-three specimens of banded croaker, Paralonchurus brasiliensis (Steindachner, 1875), collected from Pedra de Guaratiba (23o01’S, 43o38’W), coastal zone, State of Rio de Janeiro , Brazil, between September 2001 and March 2002, were necropsied to study their infracommunities of metazoan parasites. Fifteen species of metazoan parasites were collected. Paralonchurus brasiliensis is a new host record for 13 parasite species. The majority of fishes were parasitized by one or more metazoan. Larvae of Contracaecum sp. proved to be the dominant species, with highest prevalence and abundance values. The parasite species of P. brasiliensis showed the typical aggregated distribution pattern. Prevalence and abundance of Procamallanus (Spirocamallanus) pereirai was positively correlated with the host total length. Abundance of Contracaecum sp. was positively correlated with the host total length. The abundances of a pair of adult endoparasites (Aponurus laguncula - Procamallanus (S.) pereirai) showed negative covariation and one pair of larvae stages of endoparasites ( Nybelinia sp. – Contracaecum sp.) showed positive covariations between their abundances. Paralonchurus brasiliensis showed a metazoan parasite community composed by generalist species, little ordered and with scarce quantitative evidences of interspecific associations. These patterns agree with those detected in preceding studies about the parasite communities of Neotropical sciaenid fishes.
Studies on monogenetic trematodes. XL. New species from marine and freshwater fishes.
This paper presents descriptions of new species as follows: Anacanthorus brevis from Brycon melanopterus (Cope) ; Dactylogyrus navarroensis from Hesperoleucas navarroensis Snyder; Diplectanum jaculator and D. toxotes from Toxotes jaculator (Pallas) ; Parahaliotrema affinis from Chaetodon auriga Forskal and C. lunula (Lacepede); P. brevis from Acanthostracion quadricornis (Linnaeus); P. cornutus from Bodianus pulchellus Poey; P. grandis from Chaetodon auriga, C. lunula and C. setifer Bloch; P. pacificus from Chaetodon nigrorostris (Gill); and P. zebrasoma from Zebrasom.a veliferum (Bloch). All hosts were frozen initially for a minimum of 48 hours except Brycon melanopterus (Cope), which was placed directly into 10% formalin. Further preparation concerning mounting, observation, measurement, illustration, and descriptions including nomenclature were employed as given by Mizelle and Kritsky (1967), Kritsky and Mizelle (1968) and Mizelle, Kritsky and Crane (1968). All measurements are in microns. Acknowledgments.-The authors are indebted for aid in the collection of host specimens to the following (all California): M. R. Brittan, Sacramento State College, for Brycon melanopterus (Cope); J. Wittmer Crane, University of California, Davis, for Hesperoleucas navarroensis Snyder; R. P. Dempster, Steinhart Aquarium, California Academy of Sciences, San Francisco, for Bodianus pulchellus Poey, Chaetodon auriga Forskal, C. lunula (Lacepede), C. nigrorostris (Gill), C. setifer Bloch, Acanthostracion quadricornis (Linnaeus), Toxotes jaculator (Pallas) and Zebrasoma zelifer (Bloch). Especial thanks are due S. H. Weitzman, U.S. National Museum, Washington, D.C., for aid in the identification of fishes. This investigation was supported by the National Science Foundation (GB 6455). Anacanthorus brevis sp. n. (Figs. 21-23) Host and locality.-Brycon melanopterus (Cope) (Characidae), Rio Xeruiny near Terra Preta, Amazonas, Brazil, S. A. Location on host.-Gills. Type specimens.-Holotype, USNM Helm. Coll. No. 70967. Paratypes in authors' collections. Description (based on three specimens).-Dactylogyridae, Ancyrocephalinae. Length 386 (382-389), width 122 (93-152). Cephalic lobes poorly developed; head organs and cephalic glands inconspicuous. Eyespots four, anterior pair smaller, distance between members of pairs variable; accessory eyespot granules in trunk, peduncular and cephalic areas. Pharynx broadly ovate, width 30 (23-37); gut normal. I Present address: Department of Zoology, University of Illinois, Urbana