Figure 2. Geographic ranges for protostrongylid parasites in northern ungulates showing how survey and inventory have dramatically altered our understanding of diversity and distribution, before (A) and after (B) 1995. Distributions are depicted for Parelaphostrongylus andersoni in caribou (19,20); P. odocoilei in wild thinhorn sheep, mountain goat, woodland caribou, black-tailed deer, and mule deer (15,17); Umingmakstrongylus pallikuukensis in muskoxen (12,14); and a putative new species of Protostrongylidae in moose, caribou, and muskoxen (20). The range for P. andersoni in the North is presumed to coincide with caribou, although records substantiated by survey are few (19,20). Protostrongylids have not been detected in ungulates from the Arctic islands and Greenland and may be excluded from these high latitudes under current climate conditions.