Ectoparasites and endoparasites community of Ageneiosus ucayalensis (Siluriformes: Auchenipteridae), catfish from Amazon River system in northern Brazil.

This study investigated the community of ectoparasites and endoparasites in Ageneiosus ucayalensis (Auchenipteridae) of a tributary from the Amazon River system, in Northern Brazil. Of 34 fish examined, 100% were parasitized by Ichthyophthirius multifiliis, Cosmetocleithrum bulbocirrus, Demidospermus sp., metacercariae of Genarchella genarchella, Clinostomum marginatum and Herpetodiplostomum sp., Procamallanus (Spirocamallanus) belenensis, Cucullanus ageneiosus and larvae of Contracaecum sp. digeneans C. marginatum and Herpetodiplostomum sp. were dominant parasite species, while I. multifiliis was the parasite with higher infection level. Such parasite species showed an aggregated dispersion, except P. (S.) belenensis, which showed a random dispersion. The Brillouin diversity (0.53 ± 0.29) was high, while evenness (0.28 ± 0.16) and species richness of parasites (3.7 ± 1.1) were low. The size of the hosts did not influence diversity, species richness and abundance of parasites. The ectoparasites were characterized by high prevalence and abundance, while endoparasites community presented low prevalence and abundance. The main factors responsible for structuring the parasite community in A. ucayalensis were mainly the behavior of this host and the availability of endoparasites infective stages in the environment. This was the first report of I. multifiliis, C. bulbocirus, Demidospermus sp., Contracaecum sp., C. marginatum, Herpetodiplostomum sp. and G. genarchella for A. ucayalensis. The presence of endohelminth larvae suggests that A. ucayalensis is part of the diet of other fish at the top of the food web in the Amazonian ecosystem studied.

Records of new localities and hosts for crustacean parasites in fish from the eastern Amazon in northern Brazil.

The aim of this study was to investigate parasites crustacean fauna in Arapaima gigas, Cichla monoculus, Cichla ocellaris, Cichla jariina, Satanoperca jurupari, Leporinus friderici, Leporinus fasciatus, Hoplias malabaricus, Phractocephalus hemioliopterus, Serrasalmus altispinis, Pseudoplatystoma tigrinum and Potamotrygon motoro of the State Amapá and Pará, in northern Brazil. A total of 242 parasites, including Argulus elongatus, Argulus multicolor,Argulus juparanaensis, Argulus nattereri, Dolops discoidalis, Dolops longicauda, Braga patagonica, Braga fluviatilis, Livoneca guianensis and undetermined Lernaeidae, were collected from these hosts. The Argulus species had the greatest richness among the community of parasitic crustaceans. There was a low abundance of parasites among the hosts, other than D. discoidalis, was most abundant in the integument of A. gigas and P. tigrinum. Finally, the present study reported nine new hosts for the crustacean parasite species and expanded knowledge of the occurrence of some parasite species in the Jari River basin, in eastern Amazon.