Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification. Van Nostrand, Reinhold Co. New York 1728 pp. Plate 327, Figs. 4-7: U. Jurassic (U. Oxfordian), Samara Bend, Russia. 4, Longitudinal section, showing attachment to algae (a), x 100 (from Azbel', 1975); 5, longitudinal section, x 200; 6, Iectotype, x 80; 7, paratype, x 100 (5-7, from E. V. Bykova, in Kiparisova et al., 1956). courtesy of Michael Hesemann https://foraminifera.eu