New Genera of Baetidae for Some Nearctic Species Previously Included in Baetis Leach (Ephemeroptera)

Abstract

Certain Nearctic species originally described in the genus Baetis Leach lack the apomorphy possessed by other species described in Baetis and several related genera. This apomorphy is a patch of setae ventral on the femora of larvae. As a result, Baetis is here restricted to a more monophyletic concept, to include species with a patch of setae ventrally on the femora; and the nonconforming species that lack this character are placed in three new genera as follows: Fallceon , n. gen., type species Baetis quilleri Dodds as Fallceon quilleri (Dodds), n. comb., also includes Fallceon buenoi (Allen), n. comb., Fallceon byblis (Allen & Murvosh), n. comb., and Fallceon eatoni (Kimmins), n. comb.; Acerpenna , n. gen., type species Baetis macdunnoughi Ide as Acerpenna macdunnoughi (Ide), n. comb., also includes Acerpenna pygmaea (McDunnough), n. comb.; Diphetor, n. gen., type species Baetis hageni Eaton as Diphetor hageni (Eaton), n. comb., also includes Diphetor devinctus (Traver), n. comb.