Robertsonella gleasoni Titus, 1904:23, ♂♀. 1 ♀, 1 ♂, Grand Tower, Illinois, 9 May, 1902 (U. S. National Museum, No. 6858, leg. H.A. Gleason); Michener, 1938Michener, C.D. 1938. The bees of the genera Chelostomopsis, Formicapis, Robertsonella and Prochelostoma (Hymen.: Megachilidae). Entomological News 49:127-132.:131, Holotype (United States National Museum). Synonymized with Robertsonella simplex (Cresson, 1864) by Michener, 1938Michener, C.D. 1938. The bees of the genera Chelostomopsis, Formicapis, Robertsonella and Prochelostoma (Hymen.: Megachilidae). Entomological News 49:127-132.:130. - Cockerell, 1908Cockerell, T.D.A. 1908. New and little-known bees. The Canadian Entomologist 40:234-235. (distribution); Michener, 1936Michener, C.D. 1936. Some North American Osmiinae (Hymenoptera, Apoidea). American Museum Novitates 875:1-30. (distribution). - As Hoplitis gleasoni: - 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).
Robertsonella cratægina Cockerell, 1909:28, ♂. ♂, Lee County, Texas, March 15, 1909 and April 14, 1901 (leg. Birkmann); Michener, 1938Michener, C.D. 1938. The bees of the genera Chelostomopsis, Formicapis, Robertsonella and Prochelostoma (Hymen.: Megachilidae). Entomological News 49:127-132.:131, Type (Cockerell collection at Boulder, Colorado). - Mitchell, 1962Mitchell, T.B. 1962. Bees of the Eastern United States. Volume II. Technical bulletin (North Carolina Agricultural Experiment Station) 152:1-557.:65 ( listed as synonym of Hoplitis gleasoni (Titus, 1904)); 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.:2019 ( listed as synonym of Hoplitis gleasoni (Titus, 1904)). - As Robertsonella simplex crataegina: - Michener, 1938Michener, C.D. 1938. The bees of the genera Chelostomopsis, Formicapis, Robertsonella and Prochelostoma (Hymen.: Megachilidae). Entomological News 49:127-132. (distribution); Michener, 1949Michener, C.D. 1949. Records and descriptions of american Megachilid bees (Hymenoptera). Journal of the Kansas Entomological Society 22 (2):41-59. (distribution).