1. Mid- and hind femora each with 2 major setae on ventral margin; ventral filtering friinge of each mid- and hind femur in fan-like arrays. [Note: only one location for this species has been reported by OEPA; very rare]. . . . . . . . . . . . . . . . . . . . . . . . . . .Brachycentrus nigrosoma
Mid- and hind femora each with 1 major seta on ventral margin; ventral filtering fringe of each femur nearly uniform in length. Frontoclypeus with cluster of pale muscle scars near posterior apex; mid- and hind femora generally pale with fuscose dorsal and ventral margins. Rare. Reported from a few counties in unglaciated Ohio. . . . . . . . . . . Brachycentrus numerosus
Key to Species of Brachycentrus Nymphs