Species of Prochilodus Agassiz 1829 are among the most abundant fishes of South America basins and has good potential for pisciculture. During a study of the helminth parasites of Prochilodus lineatus (Valenciennes, 1837) (Characiformes) from Mogi Guaçu River, Brazil, a new species of Tereancistrum was collected. Tereancistrum pirassununguensis n. sp. can be distinguished from the other Tereancistrium species mainly by having a reduced accessory anchor sclerite with a little groove at the end; MCO as a sclerotized coiled tube forming two counterclockwise rings; an accessory piece as an inverted C, rod-like, not articulated at the base of the MCO; curved ventral bar; hooks similar with erect thumb and slightly curved shaft and point, slightly expanded shank proximally. This is the first record of a species of Tereancistrum in the southeastern of Brazil.

Two new species of Pavanelliella (Dactylogyridae) were described and some details about the morphology of Pavanelliella pavanellii Kritsky & Boeger, 1998 were added based on specimens collected from pimelodid fishes from Mogi Guaçu River, Brazil. Pavanelliella takemotoi sp. n., collected from nasal cavities of Pimelodus maculatus Lacepède, 1803 differs from its congeners by having a male copulatory organ (MCO) with 2–5 rings, vaginal canal sinuous without loops in distal portion of vaginal canal and anteriorly directed vagina containing five irregular rings around the vestibule. Pavanelliella laertei sp. n. collected from P. heraldoi Azpelicueta, 2001 is separated from the other species of the genus by lacking a vaginal vestibule and by distal end shape of accessory piece, which resemble flames or is bifurcated with one flank hooked in P. laertei sp. n. The specimens of P. pavane...

Here, we performed a quantitative analysis of the parasite communities in 21 species of fish from Guandu River, Brazil; we evaluated the effects of some host traits (body size, social behavior, fish's habitat, trophic category and ability to migration) on the diversity of their communities of metazoan parasites. To measure quantitative diversity, we used parasite species richness, as well as the average taxonomic distinctness of the assemblage and its variance. The parasite species richness, the taxonomic distinctness and the variance were unaffected by the number of host individuals examined per species. Fish body length proved to be the main predictor of parasite species richness, although it did not correlate with parasite taxonomic distinctiveness. The mains host features associated with the taxonomic diversity of parasites were schooling behavior and omnivores trophic category. Para...

The morphological and quantitative data of the larvae of Anisakidae that parasitize Lophiusgastrophysus Miranda-Ribeiro, 1915 were recorded from a marine fish of commercial importance, onthe coast of the Rio de Janeiro state. Thirty six specimens of L. gastrophysus were necropsied. Thefishes were obtained in Cabo Frio, north coast of the state of Rio de Janeiro (23º S and 42º W) and themunicipality of Rio de Janeiro, from the coast of Rio de Janeiro state (21-23° S and 41-45° W). Wefound five species of anisakid larvae: Anisakis type I, Terranova sp., Contracaecum sp.,Hysterothylacium sp. and Raphidascaris sp. The larvae of Anisakis type I were found with prevalence(P) of 22.2% and mean abundace (MA) of 0.53 larvae per host necropsied. The third stage larvae ofTerranova sp. were collected with a P=8.3% and MA=0.08. Contracaecum sp. was observed atP=8.3% and MA=0.08. Hysterothylacium ...

Un nuevo género y especie de Monogenea, Olivacotyle hemanthiasi n. gen., n. sp., se proponen para acomodar especímenes colectados de las branquias de la cabrilla doncella Hemanthias signifer (Garman, 1899) (Serranidae) en el Perú, Océano Pacífico Sudamericano (45°54'S, 81°05'W). Si bien es un miembro de Diclidophorinae Cerfontaine, 1895 que incluye parásitos de teleósteos marinos, O. hemanthiasi n. sp. difiere de los otros 15 miembros de esta subfamilia por la combinación de las siguientes seis características: (1) pinzas haptorales con la esclerita anteromedial y una esclerita anterolateral fusionadas formando un anillo, la otra esclerita anterolateral no fusionada con ninguna esclerita del cuadrante anterior interno, extensión lamelar parcialmente reducida y escleritas posterolateral distal no fusionadas distalmente; (2) pinzas dispuestas en semicírculo alrededor del borde...

A parasitological survey searching monogeneans infesting marine fish was carried out during June 2018 and January 2020 from the coastal zone of Puerto Pizarro, Tumbes (northern Peru) and from the coastal zone of Chorrillos, Lima (central Peru). The gills, skin, nasal cavities, or branchial gill-cover of seven species were sampled. Ten monogenean species assigned to six families and nine genera were identified. The monogeneans Callorhynchocotyle callorhynchi (Manter, 1955); Capsala biparasiticum (Goto, 1894) Price, 1938; Euryhaliotrema sagmatum Kritsky & Boeger, 2002; Listrocephalos kearni Bullard, Payne &Braswell, 2004; Magniexcipula lamothei Bravo-Hollis, 1981; Nasicola klawei (Stunkard, 1962) Yamaguti, 1968; and Pseudorhabdosynochus anulus Violante-Gonzalez & Rojas-Herrera, 2011 are registered for the first time in Peru. While Capsala gregalis (Wagner & Carter, 1967) Ch...