Lepidoptera collected in the Canadian Arctic during the Tundra Northwest 99 expedition

During the Swedish-Canadian icebreaker-based expedition to the Nearctic in summer 1999 (July and early August), moths and butterflies (Lepidoptera) were collected during short, helicopter-aided visits to eight sites in the Canadian archipelago, three sites on the Canadian mainland near the arctic coast and also at Thule Air Force Base in north Greenland. Some of the visited sites (notably those on Melville Peninsula, Somerset Island and King William Island) have not previously been investigated with respect to their insect faunas. Several records thus represent species range extensions. They generally corroborate an earlier hypothesis, based on a floristic zonation scheme, which has been used as a framework for understanding the distribution of Arctic butterflies.