Freshwater littoral copepods of British Columbia and Alberta (Canada)

This is part of an ongoing study on the freshwater littoral copepods of northwestern North America, comprising Alaska, Yukon, western Northwest Territories, British Columbia, Alberta, and Saskatchewan. In this paper we report 13 species of calanoids and 16 species of cyclopoids found in 142 samples collected from northern British Columbia and Alberta on either side of the Rocky mountains. We discuss morphology and distribution of some of these species.     

Composition and distributional patterns in arctic rotifers

Based on collections of rotifers from 212 localities in arctic North America, the patterns of distribution and composition are evaluated. An attempt is made to discern the dominant components of the rotifer community in arctic habitats. One hundred and sixty five species of rotifers are reported, three of which represent new records for North America. With increasing latitude and decreasing summer temperatures, a decline in species richness and change in species composition is observed. Some rotifers that previously were not adequately described are redescribed and illustrated. The significance of the dispersal capacity of rotifers in the arctic is discussed.     

The distribution of chydorid Cladocera in Canada

The distribution of chydorid Cladocera in Canada is given based on the examination of 584 samples collected from all the provinces and territories from 1978 through to 1984. Some species show regional distributions, while others are widely distributed. The preferences shown by some species to particular substrates are discussed. Further evidence is presented to show that some taxa previously claimed to be conspecific in Europe and North America may be different. In some instances the adult males tend to be more highly differentiated than the females, particularly in the structure of the postabdomen. The importance of taxonomic and distributional studies in understanding the biogeography of North American chydorids is discussed.