ADDITIONS TO THE TAXONOMY, ZOOGEOGRAPHY, AND BIOLOGY OF ANALETRIS EXIMIA (ACANTHAMETROPODINAE: SILPHLONURIDAE: EPHEMEROPTERA)
AbstractThe previously undescribed adult male and female of Analetris eximia Edmunds are treated. Additional features of nymphs are illustrated. In the Saskatchewan River system the species is found in areas unaffected by reservoirs; nymphs develop in May?, June, and July; adults emerge in late July. Nymphs are carnivorous (chironomids were the main food item in field collected specimens), live in backwaters adjacent to the main river current, and are morphologically adapted to life on an unstable silty substrate. Invasion of the Saskatchewan system was apparently via Missouri tributaries from the Colorado system. It occurred in recent times in the latter but apparently not the former. Because of habitat destruction, the species is considered endangered.