Megachile fidelis Cresson, 1878:120, Mitchell, 1937Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic Region. Part VII. Taxonomy of the subgenus Sayapis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63 (2):175-206.:182, Type ♂ (A.N.S.P., no. 2460). - Cockerell, 1899Cockerell, T.D.A. 1899. Notes on american bees (Concluded from p. 129). The Entomologist 32:154-159. (distribution); Cockerell, 1902Cockerell, T.D.A. 1902. Flowers and insects in New Mexico. American Naturalist 36 (430):809-817. (distribution); Cockerell, 1902Cockerell, T.D.A. 1902. Hymenoptera of southern California, II. Bulletin of the Southern California Academy of Science 1 (10):137-140. (distribution); Mitchell, 1937Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic Region. Part VII. Taxonomy of the subgenus Sayapis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63 (2):175-206. (distribution); Wilson et al., 2010Wilson, J.S., L.E. Wilson, L.D. Loftis & T. Griswold 2010. The montane bee fauna of north central Washington, USA, with floral associations. Western North American Naturalist 70 (2):198-207. (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).
Megachile fidelis concinnula Cockerell, 1899:158, ♂. ♂, Colorado Springs, Colorado, middle of July (leg. Ckll.). - Cockerell, 1899Cockerell, T.D.A. 1899. Notes on american bees (Concluded from p. 129). The Entomologist 32:154-159. (distribution); Mitchell, 1937Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic Region. Part VII. Taxonomy of the subgenus Sayapis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63 (2):175-206.:180 ( listed as synonym of Megachile fidelis Cresson, 1878).
Megachile nivalis Friese, 1903:246, ♂♀. 1 ♂, 4 ♀♀, Pikes Peak (Colorado), Juli (leg. Fruhstorfer); Mitchell, 1935Mitchell, T.B. 1935. A revision of the genus Megachile in the Nearctic Region. Part III. Taxonomy of subgenera Anthemois and Delomegachile (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 61 (3):155-205.:175, Type ♀ (Zool. Mus. Berlin Univ.). - Cockerell, 1926Cockerell, T.D.A. 1926. Descriptions and records of bees. - CXIII. The Annals and Magazine of Natural History ser. 9: v. 18 (108):621-627. (distribution); Mitchell, 1935Mitchell, T.B. 1935. A revision of the genus Megachile in the Nearctic Region. Part III. Taxonomy of subgenera Anthemois and Delomegachile (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 61 (3):155-205. (distribution); Mitchell, 1937Mitchell, T.B. 1937. A revision of the genus Megachile in the Nearctic Region. Part VII. Taxonomy of the subgenus Sayapis (Hymenoptera: Megachilidae). Transactions of the American Entomological Society 63 (2):175-206.:180 ( listed as synonym of Megachile fidelis Cresson, 1878); Mitchell, 1962Mitchell, T.B. 1962. Bees of the Eastern United States. Volume II. Technical bulletin (North Carolina Agricultural Experiment Station) 152:1-557. (distribution).