- As Megachile frugalis frugalis: - Mitchell, 1962Mitchell, T.B. 1962. Bees of the Eastern United States. Volume II. Technical bulletin (North Carolina Agricultural Experiment Station) 152:1-557. (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); Pascarella et al., 1999Pascarella, J.B., Waddington, K.D. & Neal, P.R. 1999. The Bee Fauna (Hymenoptera: Apoidea) of Everglades National Park, Florida and adjacent areas: Distribution, Phenology, and Biogeography. Journal of the Kansas Entomological Society 72 (1):32-45. (distribution); Pascarella, 2006Pascarella, J.B. 2006. The bees of Florida. . (distribution).
Megachile frugalis atrescens Cockerell, 1931:537, ♂♀. Holotype ♂, Yucatan: Chichenitza (Museum of Comparative Zoology, Harvard University, leg. Bequaert); Raw, 2007Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile) of the Neotropics. Zootaxa 1601:1-127.:93, Type ♂ (MCZ, 16264). - Cockerell, 1932Cockerell, T.D.A. 1932. Bees (Hymenoptera, Apoidea) collected at Chichen Itzá, Yucatan, by the Harvard expeditions of 1929-1930. Bulletin of the Brooklyn Entomological Society 27:9-17. (distribution); Raw, 2007Raw, A. 2007. An annotated catalogue of the leafcutter and mason bees (genus Megachile) of the Neotropics. Zootaxa 1601:1-127.:93 ( listed as synonym of Megachile frugalis Cresson, 1872).