Halictus petrellus Cockerell, 1903:84, ♀. ♀, San Pedro, Calif., July 11, 1901 (leg. Cockerell); Gibbs, 2009Gibbs, J. 2009. New species in the Lasioglossum petrellum species group identified through an integrative taxonomic approach. The Canadian Entomologist 141:371-396.:376, Holotype ♀, examined (NMNH, No. 27771); Gardner & Gibbs, 2020Gardner, J. & J. Gibbs 2020. The 'red-tailed' Lasioglossum (Dialictus) (Hymenoptera: Halictidae) of the western Nearctic. European Journal of Taxonomy 725:1-242.:167, Holotype ♀ (USNM). - As Dialictus petrellus: - 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). - As Lasioglossum petrellum: - Gardner & Gibbs, 2020Gardner, J. & J. Gibbs 2020. The 'red-tailed' Lasioglossum (Dialictus) (Hymenoptera: Halictidae) of the western Nearctic. European Journal of Taxonomy 725:1-242. (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).
Halictus coronadensis Cockerell, 1916:56, ♂. Type ♂, Coronado Islands, L. Calif., Aug. 21 (leg. T. & W. Ckll.); Gibbs, 2009Gibbs, J. 2009. New species in the Lasioglossum petrellum species group identified through an integrative taxonomic approach. The Canadian Entomologist 141:371-396.:376, Holotype ♂ (NMNH, No. 23331). - Cockerell, 1916Cockerell, T.D.A. 1916. The bees of the Coronado Islands. The Canadian Entomologist 48 (2):54-58. (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.:1970 ( listed as synonym of Dialictus petrellus (Cockerell, 1903)); Gibbs, 2009Gibbs, J. 2009. New species in the Lasioglossum petrellum species group identified through an integrative taxonomic approach. The Canadian Entomologist 141:371-396.:37 ( listed as synonym of Lasioglossum petrellum (Cockerell, 1903)); Gardner & Gibbs, 2020Gardner, J. & J. Gibbs 2020. The 'red-tailed' Lasioglossum (Dialictus) (Hymenoptera: Halictidae) of the western Nearctic. European Journal of Taxonomy 725:1-242.:167 ( listed as synonym of Lasioglossum petrellum (Cockerell, 1903)).