Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 282, Figs. 1-4: L. Permian (Sakmarian), M. Wolfcampian, Gym Limestone, EI Paso Quadrangle, New Mexico, USA. 1, Tangential polished surface, x 8; 2, antethecal view of exterior, x 8; 3, axial section of lectotype, x 8; 4, sagittal section, x 8 (from Dunbar and Skinner, 1931). courtesy of Michael Hesemann https://foraminifera.eu
