• Microtendipes rydalensis (Edwards, 1929)

is a Chironomidae species which is widely distributed species in Europe with a characteristic mentum shape, but rarely recorded in Poland. It was reported in eastern Poland by Tarkowska-Kukuryk & Kornijów (2008) in Lake Kleszczów and Tarkowska-Kukuryk (2014) in Lake Skomielno. The record of M. rydalensis in Rawka River is the first such case in central Poland. The species prefers littoral and sublittoral sediments of still water, but sporadically inhabits sediments or submerged mosses in running water (Andersen et al. 2013).