Chaoborus (Chaoborus) obscuripes

Chaoborus (Chaoborus) obscuripes (van der Wulp, 1859) Material examined. 1 larva, Lake Geryshaska (L 7), 15 September 2021. Distribution. Palaearctic. The species is widespread mainly in Northern and Western Europe, but also in Poland and the European part of Russia (Borkent 1981; de Jong 2016). Habitat. Small, shallow nutrient-poor, meso- and polyhumic ponds with pH 4.5–5.5 (Nilssen 1974; Joniak and Domek 2006; Kuper and Verberk 2011), often fishless. Larger larvae with darker pigmentation are more sensitive to visually dependent predators (Stenson 1981). Remarks. The species seems to occur sporadically and mostly in small numbers (Borkent 1981), which is probably related to its ecological requirements for water chemistry and the absence of fish. The first annotated checklist of Ukrainian Chironomidae consists of 302 species (Baranov 2011 a). However, this list requires revision because it contains invalid species identified solely on the basis of larvae using outdated identification keys. In recent decades, the study of taxonomy, ecology, and biogeography of chironomids in Ukraine has intensified (Baranov 2011 b, 2013, 2014; Baranov and Przhiboro 2014; Baranov and Ferrington 2013; Moubayed-Breil and Baranov 2018; Didenko et al. 2021). Our survey revealed a significant gap in the taxonomic knowledge of Ukrainian chironomids. The high number of new records suggests that the chironomid fauna, especially from flowing waters is far from being fully discovered. Undoubtedly, it is necessary to continue the study of the chironomid fauna of the Eastern Carpathians. Particularly, the collection of the pupal exuvia could be a very useful tool in studying species richness, ecology, and distribution, but also for water quality assessment and monitoring purposes.