Mutilla pygmea Blake, 1879:250, ♀. 4 ♀♀, Texas, Colorado, Nevada. - Blake, 1879Blake, C.A. 1879. Catalogue of the Mutillidae of North America, with descriptions of new species. Transactions of the American Entomological Society 7:243-254. (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.:1292 ( listed as synonym of Sphaeropthalma nanula (Dalla Torre, 1897)). - As Mutilla pygmaea: - Fox, 1899Fox, W.J. 1899. The North American Mutillidae. Transactions of the American Entomological Society 25:219-300.:259 ( listed as synonym of Mutilla nanula Dalla Torre, 1897); Pagliano et al., 2020Pagliano G., D.J. Brothers, R. Cambra, A.S. Lelej, P. Lo Cascio, M.M. Palmerini, P.L. Scaramozzino, K.A. Williams & M. Romano 2020. Checklist of names in Mutillidae (Hymenoptera), with illustrations of selected species. Bolletino del Museo Regionale di Scienze naturali Torino 36 (1-2):5-425.:28 ( listed as synonym of Dilophotopsis concolor (Cresson, 1865)). - As Sphaerophthalma pygmea: - Blake, 1886Blake, C. 1886. Monograph of the Mutillidae of North America. Transactions of the American Entomological Society 13:179-286. (distribution).
Mutilla nanula Dalla Torre, 1897:65, no descr. Replacement name for Mutilla pygmaea Blake, 1879 by Dalla Torre, 1897Dalla Torre, C.G. 1897. Catalogus hymenopterorum hucusque descriptorum systematicus et synonymicus. Volumen VIII: Fossores (Sphegidae). Breitkopf & Härtel, Leipzig. 1-749.:65 (nec Gerstaecker). - Dalla Torre, 1897Dalla Torre, C.G. 1897. Catalogus hymenopterorum hucusque descriptorum systematicus et synonymicus. Volumen VIII: Fossores (Sphegidae). Breitkopf & Härtel, Leipzig. 1-749. (distribution); Fox, 1899Fox, W.J. 1899. The North American Mutillidae. Transactions of the American Entomological Society 25:219-300. (distribution); Melander, 1903Melander, A.L. 1903. Notes on North American Mutillidae, with descriptions of new species. Transactions of the American Entomological Society 29 (4):291-330. (distribution); Pagliano et al., 2020Pagliano G., D.J. Brothers, R. Cambra, A.S. Lelej, P. Lo Cascio, M.M. Palmerini, P.L. Scaramozzino, K.A. Williams & M. Romano 2020. Checklist of names in Mutillidae (Hymenoptera), with illustrations of selected species. Bolletino del Museo Regionale di Scienze naturali Torino 36 (1-2):5-425.:28 ( listed as synonym of Dilophotopsis concolor (Cresson, 1865)). - As Sphaeropthalma nanula: - 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).