Zoogeographical relationships of aquatic insects (Ephemeroptera, Plecoptera, and Tricoptera) from eastern James Bay drainage

Abstract

An analysis of the aquatic insect fauna of the eastern James Bay drainage was conducted on the basis of specimens assembled in 1973-1982 during several impact studies related to the major hydroelectric projects conducted in the area. 220 species were collected in the orders Plecoptera (22), Ephemeroptera (50), and Trichoptera (148). Two main pathways for colonization are suggested, one from Northwestern refugia and another from Southern refugia, probably through the Mississippi-St. Lawrence waterways. Dispersal appears to have been greatest in Trichoptera and least in Plecoptera; respective importances of the transcontinental fauna vary from 14{%} (Plecoptera) to 47.3{%} (Trichoptera).