ABSTRACT
ABSTRACT This study investigated the parasitic fauna of Cichlasoma bimaculatum of a tributary from the Amazon River system, northern Brazil. The prevalence of infection was 94.6 % and, in total, 428 267 parasites, such as Ichthyophthirius multifiliis, Piscinoodinium pillulare (Protozoa), Gussevia arilla (Monogenoidea), Posthodiplostomum sp. (Digenea) and Procamallanus (Spirocamallanus) inopinatus (Nematoda) were collected. However, the dominance was mainly of I. multifiliis, while P. (S.) inopinatus was the parasite species with the lower levels of prevalence and abundance of infection. These parasite species showed an aggregated dispersion pattern. The parasitic fauna was characterized by the presence of few species of parasites with high prevalence and abundance, specifically ectoparasites, and a low number of endoparasites. The observed pattern is explained by the mode of life of the host and it is suggested that C. bimaculatum occupies a low trophic level at the food web.
RESUMEN Este estudio investigó la fauna parasitaria de Cichlasoma bimaculatum (Cichlidae) en un afluente del sistema del Río Amazonas, en el norte de Brasil. La prevalencia parasitaria fue del 94,6 % y en total, 428267 parásitos fueron colectados, entre estos Ichthyophthirius multifiliis, Piscinoodinium pillulare (Protozoa), Gussevia arilla (Monogenoidea), Posthodiplostomum sp. (Digena) y Procamallanus (Spirocamallanus) nopinatus (Nematoda). Aunque el predominio fue de I. multifiliis, el nematodo P. (S.) inopinatus fue la especie menos frecuente y abundante. Estas especies de parásitos mostraron un patrón de dispersión agregada. La fauna parasitaria se caracterizó por la presencia de algunas pocas especies de parásitos con mayor prevalencia y abundancia de ectoparásitos y una baja presencia de endoparásitos. Se discute que lo anterior puede deberse al modo de vida del hospedero y sugieren que C. bimaculatum ocupa un bajo nivel en la cadena trófica.
ABSTRACT
This work is the first study on parasitic fauna of Curimata cyprinoides Linnaeus, 1766 (Curimatidae) and the host-parasite relationship. The total of 154,740 parasites such as Ichthyophthirius multifiliis (Ciliophora), trophozoite of Spironucleus sp. (Hexamitidae), Urocleidoides sp. (Monogenoidea), Digenea gen. sp. and Polymorphus sp. (Polymorphidae) were collected. The component community showed low diversity (HB = 0.004 ± 0.020) and parasite species richness (1.4 ± 0.6). However, I. multifiliis and Urocleidoides sp. were prevalent and with higher intensity on the host population and also aggregated the distribution pattern. The occurrence of these ectoparasites in C. cyprinoides may be a consequence of its alimentary diet. Positive correlation between the abundance and size of I. multifiliis and the relative condition factor of the host were observed and discussed. These data represent increased knowledge of the biology of these parasites. Furthermore, this study expanded the geographic distribution of some parasite species for this new host from Brazil.