Hoplitella pentamera Cockerell, 1910:170, ♂. ♂, Claremont, California (leg. C.F. Baker); Michener, 1947Michener, C.D. 1947. A revision of the american species of Hoplitis (Hymenoptera, Megachilidae). Bulletin of the American Museum of Natural History 89:257-318.:274, Type (United States National Museum). - Michener, 1947Michener, C.D. 1947. A revision of the american species of Hoplitis (Hymenoptera, Megachilidae). Bulletin of the American Museum of Natural History 89:257-318.:272 ( listed as synonym of Ashmeadiella howardi Cockerell, 1910).
Ashmeadiella howardi Cockerell, 1910:22, ♂♀. Holotype ♀, San Gabriel Mts., Los Angeles County, California, 3000 feet, June 16, 1909 (leg. F. Grinnell, Jr.); Michener, 1947Michener, C.D. 1947. A revision of the american species of Hoplitis (Hymenoptera, Megachilidae). Bulletin of the American Museum of Natural History 89:257-318.:274, Type (United States National Museum). - Michener, 1936Michener, C.D. 1936. Some North American Osmiinae (Hymenoptera, Apoidea). American Museum Novitates 875:1-30. (distribution). - As Hoplitis howardi: - 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).
Hoplitina hesperia Crawford, 1916:103, Michener, 1947Michener, C.D. 1947. A revision of the american species of Hoplitis (Hymenoptera, Megachilidae). Bulletin of the American Museum of Natural History 89:257-318.:274, Type (United States National Museum). - Michener, 1947Michener, C.D. 1947. A revision of the american species of Hoplitis (Hymenoptera, Megachilidae). Bulletin of the American Museum of Natural History 89:257-318.:273 ( listed as synonym of Hoplitis howardi Cockerell, 1910).