Halictus exiguus Smith, 1879:37, ♀. ♀, Mexico (British Museum); Cockerell, 1905Cockerell, T.D.A. 1905. Notes on some bees in the British Museum. Transactions of the American Entomological Society 31:309-364.:353, Type ♀ (British Museum); Eickwort, 1970Eickwort, G.C. 1970. The identity of Dialictus umbripennis in Central America (Hymenoptera: Halictidae). Journal of the Kansas Entomological Society 43:34-43.:42, Holotype ♀ (British Museum (Natural History)). - Dalla Torre, 1896Dalla Torre, C.G. 1896. Catalogus Hymenopterorum hucusque descriptorum systematicus et synonymicus, X. Apidae (Anthophila). Sumptibus Guilelmi Engelmann, 1-643. (distribution); Cockerell, 1899Cockerell, T.D.A. 1899. Catálogo de las Abejas de Mexico. Biblioteca Agricola de las Secretaria de Fomento, Mexico, 1-20. (distribution); Sandhouse, 1924Sandhouse, G.A. 1924. New American species of bees belonging to the genus Halictus (Chloralictus). Proceedings of the United States National Museum 65 (2532):1-43. (distribution). - As Dialictus exiguus: - Eickwort, 1970Eickwort, G.C. 1970. The identity of Dialictus umbripennis in Central America (Hymenoptera: Halictidae). Journal of the Kansas Entomological Society 43:34-43. (distribution), 42 (comb. nov.). - As Lasioglossum exiguum: - 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).