Figures: 9-10, 38, 52, 70, 104, 114, 119, 124, 150-154, 175-176, 194, 227
In addition to the Rhithrogeninae characteristics, the following combination of characteristics will identify the genus:
Larvae of Epeorus are identified by the enlarged incisors on the galealaciniae (Fig. 52), the vestigial median caudal filament (Fig. 9), and the dense row of setae on the anterior margin of the head capsule (Fig. 38).
The combination of the absence of a transverse suture on the mesonotum (Fig. 114), segment 1 of the foretarsi equal to or longer than segment 2 (Fig. 124), and relatively broad hindwings without distal dark staining (Fig. 176) will differentiate adults of Epeorus from other Rhithrogeninae genera, except the Nearctic Ironodes. Some Nearctic species of Epeorus have penes that are separated nearly to the base and lack titillators (Fig. 152), such as in Ironodes, but can be differentiated by the poorly developed basal crossveins in the forewings (Fig. 175) and the reddish abdominal terga with pale median spots (Fig. 194).
Holarctic; Oriental; Neotropical south to northern Columbia (Fig. 227).