Mutilla pluto Fox, 1899:255, ♂. 5 ♂♂, Texas. - As Sphaeropthalma pluto: - 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); 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. (distribution).
Mutilla palamedes Fox, 1899:264, ♂. Holotype ♂, Texas. - 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.:1293 ( listed as synonym of Sphaeropthalma pluto (Fox, 1899)); 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.:43 ( listed as synonym of Sphaeropthalma pluto (Fox, 1899)).