Published online by Cambridge University Press: 14 July 2015
The composition of Permian members of the superfamily Subulitacea is considered, and 12 new species of Subulitacea are described from the silicified fauna of the Permian System of West Texas and New Mexico. Other elements of the gastropod fauna were previously described by Yochelson (1956a, 1960) and Batten (1958).
The new genus Ischnoptygma is established for subulitaceans possessing a plate-like columellar fold, and includes the new species Ischnoptygma archibaldi and I. valentinei. The genus is placed within the new family Ischnoptygmidae. New species of Subulitidae are Ceraunocochlis deformis, C. elongata, C. kidderi, C. trekensis, Strobeus girtyi, Soleniscus diminutus, S. variabilis, Cylindritopsis hamiltonae, and C. spheroides. The status of the genus Labridens is questioned, but provisionally retained. The assignment of the family Meekospiridae to the Subulitacea is questioned, and a single new species, Meekospira mimiae, is described.