New revision at ZooKeys, 2018 #755: A revision of the cleptoparasitic bee genus Epeolus Latrielle for Nearctic species, north of Mexico (Hymenoptera, Apidae) by Thomas M. Onuferko.
Epeolus ainsliei (new) in Kent County. Like E. scutellaris, but lower thorax (scutellum) and the points (axillae) are all red.
Epeolus americanus – Northern mostly north of Lake Superior
Epeolus autumnalis – southern
Epeolus bifasciatus – southern
Epeolus canadensis – southern
Epeolus interruptus – southern
Epeolus minimus – Georgian Bay to Toronto and north
Epeolus pusillus – southern
Epeolus scutellaris – southern
Note: Epeolus ilicis – has been dropped from the Ontario list of species. Only present in southeastern states and coastal border to N. Carolina.
Romankova in the Journal of the Entomological Society of Ontario, 2004 listed E. ilicis. “What Romankova (2004) identified as E. ilicis, which constituted a new record of that species in Canada, might actually be E. gibbsi and/or E. inornatus. Unfortunately, the vouchered material from that study (three specimens from Ontario) cannot be traced, so the presence of E. ilicis in Canada has not been confirmed in the present study. Epeolus ilicis has been reported from the New England states, though the only examined specimen from that region (a male from Massachusetts) that had been identified as E. ilicis (by Richard L. Brumley) appears to actually be E. inornatus based on the very short straight subapical hairs on S4 and S5. In Canada, E. gibbsi is only confirmed from southern Manitoba, so the specimens from southern Ontario studied by Romankova could represent any of the three species.”, per Onuferko (2018).
Southern Ontario Epeolus
Legs mostly dark:
Epeolus bifasciatus – The easiest; only two yellow stripes on abdomen. Thorax segment 2 (scutellum) is bright red.
Legs with ALL thighs (femora) black:
E. autumnalis has the yellow stripe on the collar (prothorax) unbroken.
E. canadensis has the collar is separated or broken at centre.
Mid thorax stripes in E. autumnalis go straight down.
Mid thorax stripes in E. canadensis are joined at mid thorax, forming a V- or U-shape.
E. canadensis flies from late June to early August.
E. autumnalis flies only in September.
Legs all reddish-yellow; only hind thigh (femora) black:
Epeolus lectoides – Comparatively, E. lectoides is the only one with very thin white stripes on the abdomen (although slightly wider at side edges); all stripes are interrupted or broken at centre.
Legs all reddish:
E. scutellaris thorax sides have one curved line of white hair.
E. pusillus thorax sides entirely covered with white hair.
E. scutellaris thorax segment 2 (scutellum) female entirely red.
E. pusillus thorax segment 2 (scutellum) male and female black.
E. scutellaris has the 2 stripes on abdomen segment 1 not joined at side edges of segment.
E. pusillus has the 2 stripes on abdomen segment 1 thickly joined at side edges of segment.
E. scutellaris male has dark streaks on underside of mid and hind legs. Thorax segment 2 (scutellum) is black in male, like E. pusillus. Difficult to separate the males.