Epifauna of native and alien freshwater crayfish species (Crustacea:Decapoda): a host-specific community?

摘要

Freshwater crayfishes serve as hosts to diverse epifaunal assemblages. We investigated epifauna on 3 native and 2 alien freshwater crayfish collected in Croatia (Europe). Our main goals were to compare epifauna with surrounding infauna and periphyton and to test whether epifauna differ among crayfish species. A total of 40 epibiont taxa were identified. Ciliophorans were the most abundant, whereas rotifers were the most diverse (17 taxa). Five species of branchiobdellidans were found as crayfish ectosymbionts. Two new biogeographical records of nonindigenous epibiont species, the branchiobdellidan Xironogiton victoriensis and ostracod LIncinocythere occidental, were identified on the alien North American crayfish Pactfastacus leniusculus. On native crayfishes, a few specific epibiont species were recorded: 1 copepod (Nitocra divaricata) and 4 rotifers (Lepadella astacicola, L. branchiola, L. parasitica, and Dicranophorus cambari). Results indicated a highly diverse and complex crayfish epifaunal community that differed significantly from surrounding infauna and periphyton. Our results indicated differences in the epifaunal assemblage between native and alien crayfishes that suggest the possibility of a specific connection between epifauna and hosts. We presume that future studies will reveal higher epifaunal diversity on freshwater crayfish, with some new insights in taxonomy and ecology.