Opertorbitolites douvillei Nuttall, 1925

Description:

 Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification.  Van Nostrand, Reinhold Co. New York 1728 pp. Plate 422, Figs. 6-7: L. Eocene, Dunghan Limestone, Laki Series, Baluchistan Prov., Pakistan. 6, Central part of axial section of holotype, x 16; 7, equatorial section intersecting chamberlets of median plane, x 16 (from Nuttall, 1925). courtesy of Michael Hesemann https://foraminifera.eu