First study on infestation of Excorallana berbicensis (Isopoda: Corallanidae) on six fishes in a reservoir in Brazilian Amazon during dry and rainy seasons

Abstract

We analyzed the infestation levels of Excorallana berbicensis on Acestrorhynchus falcirostris, Ageneiosus ucayalensis, Geophagus proximus, Hemiodus unimaculatus, Psectrogaster falcata and Serrasalmus gibbus in a reservoir in the Araguari River basin, northern Brazil, during the dry and rainy seasons. For P. falcata, the infestation levels due to E. berbicensis were greater during the rainy season. For all the species studied, the peak parasite prevalence was in the month of highest rainfall levels and there were two peaks of parasite abundance: one in the month with highest rainfall level and the other in the month of transition from the rainy season to the dry season. In these hosts, around 70% of the E. berbicensis specimens were collected during the rainy season. The body conditions of the hosts also did not suffer any seasonal influence. Despite the differences in seasonal rainfall levels, there was no fluctuation in transparency, turbidity, pH, electric conductivity, temperature and dissolved oxygen levels in the water, due to the stability of these parameters during the seasonal cycle investigated in this artificial Amazon ecosystem. This was the first report on the seasonality of infestation by E. berbicensis associated with fish.

Host selection and potential predation in the host-parasite interaction between the isopod Tachaea chinensis and freshwater host species

“…However, T. chinensis was found infesting different hosts at varying degrees. The low host specificity found in this study complies with that of other isopod species in the family Corallanidae ( Ho and Tonguthai, 1992 ; Gentil-Vasconcelos and Tavares-Dias, 2015 ) and other studies on T. chinensis ( Xu et al, 2021 ; Ota, 2019 ; Nagasawa et al, 2018 ). This low host specificity likely facilitates the successful existence of this isopod in different habitats.…”

New occurrence of Cirolana capricornica (Isopoda: Cirolanidae) from Epinephelus chlorostigma in Suez Governorate, Egypt

“…Although the isopods used in the present study were obtained from fish, other scientists disagree that they are real parasites. Gentil-Vasconcelos and Tavares-Dias [5] considered some species of this family, such as "Excorallana berbadensis" (Boone, 1918), as parasites of South American freshwater fishes. Excorallana.…”

Description and ontogeny of a 40-million-year-old parasitic isopodan crustacean:Parvucymoides dvorakorumgen. et sp. nov.

“…Several of the ingroups of Cymothoida have species that exhibit parasitic strategies (temporarily or permanently) during some stage of development, or for a specific duration of time. Species with parasitic life strategies are found in the following groups: Corallanidae Hansen, 1890 (see Gentil-Vasconcelos & Tavares-Dias, 2015 ; Nagasawa, Imai & Saito, 2018 ), Aegidae White, 1850 (see Nair & Nair, 1983 ; Cavalcanti et al, 2012 ), Cymothoidae Leach, 1818 (see Kottarathil et al, 2019 ; Mahmoud, Fahmy & Abuowarda, 2020 ), Epicaridea (including Bopyroidea Rafinesque, 1815 and Cryptoniscoidea Kossmann, 1880 ; see Roccatagliata & Jordá, 2002 ; Alves-Júnior et al, 2019 ), Gnathiidae Leach, 1814 (see Smit, Basson & Van As, 2003 ; Marino et al, 2004 ) and possibly Urda Münster, 1840 (see Nagler, Hyžný & Haug, 2017 ).…”