Origin and distribution of the Chironomidae (Diptera) from the Saskatchewan River, Saskatchewan, Canada
Approximately one third of the named Saskatchewan River chironomid species have Holarctic distributions, the remaining species are strictly Nearctic. Only 6 of the 143 species so far recorded from the Arctic are present in the Saskatchewan River. In contrast, 69 of the 76 named Saskatchewan River species are also found in eastern North America. Of the remaining seven, Cyphomella gibbera Saether, Chernovskiia amphitrite (Townes), Parakiefferiella (s.str.) torulata Saether, and the Holarctic Cricotopus (Isocladius) intersectus (Staeger) have previously been recorded only from Manitoba in the Nearctic. Synorthocladius semivirens Kieffer, a Holarctic species, is known only from northern and western Canada in North America, and Cryptotendipes darbyi Sublette and Stictochironomus quagga (Townes) have western distributions. Analysis of distribution records from recent subgeneric revisions of Orthocladius (Orthocladius) and Polypedilum (Polypedilum) suggest that the majority of Saskatchewan River species originated from southern refugia. This conclusion is supported by studies of other aquatic animals in western Canada, which also appear to be derived from southern refugia.
The birds of eastern North America : with original descriptions of all the species which occur east of the Mississippi River, between the Arctic circle and the Gulf of Mexico, with full notes upon their habits, etc. ,/ by C.J. Maynard...
