Branchinecta readingi, new species name for a well-known fairy shrimp fromeast of the North American Continental Divide

Branchinecta mackini Dexter, 1956 (Crustacea, Anostraca) has been thought t o occur both east and west of the Continental Divide of North America for m ore than 30 years. My study revealed that individuals from east of the Divi de are morphologically distinct from those found west of the Divide. Males consistently differed in the shape of the distal end of the antenna. The ea stern taxon is described and given the name Branchinecta readingi new speci es.