Colletes brevicornis Robertson, 1897:315, ♂. Holotype ♂, Illinois; Stephen, 1954Stephen, W.P. 1954. A revision of the bee genus Colletes in America north of Mexico (Hymenoptera, Colletidae). University of Kansas Science Bulletin 36:149-527.:411, Holotype (Illinois State Natural History Survey). - Timberlake, 1943Timberlake, P.H. 1943. Bees of the genus Colletes chiefly from Colorado. Bulletin of the American Museum of Natural History 81 (5):385-410. (distribution); Stephen, 1954Stephen, W.P. 1954. A revision of the bee genus Colletes in America north of Mexico (Hymenoptera, Colletidae). University of Kansas Science Bulletin 36:149-527. (distribution); Mitchell, 1960Mitchell, T.B. 1960. Bees of the Eastern United States. Volume I. Technical bulletin (North Carolina Agricultural Experiment Station) 141:1-538. (distribution); Hall et al., 2016Hall, H.G., D.T. Almquist & J.S. Asher 2016. A new species of Colletes (Hymenoptera: Apoidea: Colletidae) from northern Florida and Georgia, with notes on the Colletes of those states. Journal of Melittology 58:1-20. (distribution); Owens et al., 2018Owens, B.E., L. Allain, E.C. van Gorder, J.L. Bossart & C.E. Carlton 2018. The bees (Hymenoptera: Apoidea) of Louisiana: An updated, annotated checklist. Proceedings of the Entomological Society of Washington 120 (2):272-307. (distribution).
Colletes opuntiƦ Cockerell, 1906:312, ♂♀. Holotype ♀, Boulder, Colorado, July 3, 1905 (leg. W.P. Cockerell); Stephen, 1954Stephen, W.P. 1954. A revision of the bee genus Colletes in America north of Mexico (Hymenoptera, Colletidae). University of Kansas Science Bulletin 36:149-527.:411, Holotype (United States National Museum). - Timberlake, 1943Timberlake, P.H. 1943. Bees of the genus Colletes chiefly from Colorado. Bulletin of the American Museum of Natural History 81 (5):385-410. (distribution), 399 ( listed as synonym of Colletes brevicornis Robertson, 1897); Stephen, 1954Stephen, W.P. 1954. A revision of the bee genus Colletes in America north of Mexico (Hymenoptera, Colletidae). University of Kansas Science Bulletin 36:149-527.:407 ( listed as synonym of Colletes brevicornis Robertson, 1897); Mitchell, 1960Mitchell, T.B. 1960. Bees of the Eastern United States. Volume I. Technical bulletin (North Carolina Agricultural Experiment Station) 141:1-538.:34 ( listed as synonym of Colletes brevicornis Robertson, 1897).
Colletes brachyceros Graenicher, 1935:301 - Mitchell, 1960Mitchell, T.B. 1960. Bees of the Eastern United States. Volume I. Technical bulletin (North Carolina Agricultural Experiment Station) 141:1-538.:34 ( listed as synonym of Colletes brevicornis Robertson, 1897).