Bryozoan species Hyalinella punctata Hancock in the gut content of chub Leuciscus cephalus L.

Abstract

Bryozoans are widely distributed benthic invertebrates which form colonies both in running and stagnant waters. There are 19 freshwater species of Bryozoa in Europe, and only three have been recorded in Serbia so far. Statoblasts (the dormant stages of these colonial animals) are relatively frequently found in the gut contents of fish, but those of the Hyalinella punctata species (Phylactolaemata) have not been registered. Statoblasts of H. punctata were determined for the first time in the gut content of chub Leuciscus cephalus sampled from the Zapadna Morava River (West Serbia, Danube River basin) in late summer and autumn. The intactness in form supports their viability after the passage through intestines, implying that the fish may be a vector of the dispersal of H. punctata in new aquatic habitats, as well as a risk factor in the transmission of certain salmonid fish disease agents into fish farms and natural habitats.