Effect of Salinity on Chironomid Larvae (Diptera, Chironomidae) in Hypersaline Lakes of Crimea

Resumo

This paper summarizes the results of our long-term research (2007–2015) of chironomids in 38 saline and hypersaline lakes of Crimea. Chironomid larvae were found at salinities up to 340 g/L, and the frequency of their occurrence decreased as salinity rose above 30–50 g/L. We identified four species, namely, Baeotendipes noctivagus, Cricotopus gr. cylindraceus, Tanytarsus gr. Mendax, and Paratanytarsus gr. quantuplex. The numbers of chironomid larvae varied within wide limits and peaked at the levels of up to 8000/m³ in plankton, up to 9000/m² in the benthos, and up to 3000/m² on the floating mats of filamentous green algae. The abundance, biomass, and production of larvae were nonlinearly dependent on the salinity. A salinity increase led to a decreased number of species and reduced average sizes. The maximum values were observed within 150–170 g/L.