Colletes slevini Cockerell, 1925:185, ♀. Holotype ♀, Paraiso Springs, Monterey County, California, September 24, 1922 (Mus. Calif. Acad. Sci., No. 1648, leg. L.S. Slevin); 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.:266, Holotype (California Academy of Sciences). - 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); Krombein et al., 1979Krombein, K.V., P.D. Hurd, D.R. Smith & B.D. Burks 1979. Catalog of Hymenoptera in America North of Mexico. Volume 2. Apocrita (Aculeata). Smithsonian Institution Press, Washington D.C. 1199-2209. (distribution); Esperanza de Pedro, 2021Esperanza de Pedro, D. 2021. . :. (distribution); Nava-Bolaños & Osorio-Olvera, 2022Nava-Bolaños, A. & L. Osorio-Olvera 2022. Estado del arte del conocimiento de biodiversidad de los polinizadores de México. Revista Mexicana de Biodiversidad 93:1-77. (distribution). - As Colletes sleveni: - Timberlake, 1951Timberlake, P.H. 1951. Western bees of the genus Colletes (Hymenoptera: Apoidea). The Wasmann Journal of Biology 9 (2):181-238. (distribution).
Colletes eriogoni Cockerell, 1939:188, 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.:266, Holotype (Citrus Experiment Station, Riverside, California). Synonymized with Colletes sleveni Cockerell, 1925 by Timberlake, 1951Timberlake, P.H. 1951. Western bees of the genus Colletes (Hymenoptera: Apoidea). The Wasmann Journal of Biology 9 (2):181-238.:208. - 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.:262 ( listed as synonym of Colletes slevini Cockerell, 1925); Krombein et al., 1979Krombein, K.V., P.D. Hurd, D.R. Smith & B.D. Burks 1979. Catalog of Hymenoptera in America North of Mexico. Volume 2. Apocrita (Aculeata). Smithsonian Institution Press, Washington D.C. 1199-2209.:1751 ( listed as synonym of Colletes slevini Cockerell, 1925).