Relict Populations of <i>Drepanopus bungei</i> and <i>Limnocalanus macrurus grimaldii</i> (Copepoda: Calanoida) from Ellesmere Island, Northwest Territories

Abstract

Reports the occurrence of these two brackish-water copepods in the freshwater layer of Tuborg Lake, at the head of Antoinette Bay, one of the eastern extensions of the Nansen Sound-Greely Fiord system. Drepanopus bungei has been known previously only from the arctic coast of Siberia; it was also found in Disraeli Fiord on the north coast of Ellesmere Island. Tuborg Lake has been cut off from the Arctic Ocean for 3000 yr, hence these species are relict from a time when they were more widespread in the Arctic, probably owing to a generally lower salinity. The Tuborg Lake population of Limnocalanus macrurus grimaldii fits into Linquist's "non-extreme grimaldii" category has evolved only slightly, if at all, toward the macrurus form (with highly vaulted forehead). Remarks on the meromict layering and temperature/salinity profiles of the lake are included.