Corophiids (Amphipoda, Corophioidea) of the River Danube - the Results of A Longitudinal Survey

Abstract

Three species of Corophiidae (Amphipoda) were identified in the macrozoobenthos samples of the "Joint Danube Survey 2" (organized by the ICPDR). Chelicorophium sowinskyi (Martynov, 1924) and Chelicorophium robustum (G. O. Sars, 1895) were found for the first time in the Upper Danube. It is likely that C. sowinskyi has been overlooked in this area for decades, while C. robustum is a recent invader probably spreading downstream in the river. Chelicorophium curvispinum (G. O. Sars, 1895) was present in the whole navigable course of the river, whilst the other two species showed a discontinuous distribution with a gap in the Middle Danube. In the case of C. sowinskyi this gap is likely to reflect that this area is not tolerable for it for some reason, while C. robustum has probably not reached this section yet.