Crustacean species new to Spitsbergen with notes on the polymorphism and the subfossil preservation of Cytherissa lacustris (G. O. Sars)

Abstract

The copepods Limnocalanus macrurus G. O. Sars and Eucyclops serrulatus (Fisch.) and the ostracode Cytherissa lacustris (G. O. Sars), hitherto unknown on Spitsbergen, were found in Lake Rewatnet, the last species also in Lake Svartvatnet. Samples from parthenogenetic populations of C. lacustris showed a complete lack of electrophoretically detectable variability at four enzyme-encoding loci, two of which are highly variable in mainland populations. However, morphological variation in the carapace length and nodation was no less than in the mainland populations. The carapace valves of C. lacustris do not preserve well in the sediments of Rewatnet.