Tortonella bondartschuki Didkovskiy, 1957

Description:

 Loeblich, A. R., Tappan, H. N., 1987: Foraminiferal genera and their classification.  Van Nostrand, Reinhold Co. New York 1728 pp. Plate 346, Figs. 18-28: M. Miocene (U. Tortonian), Ukraine. 18, Transverse section showing early triloculine stage and later planispiral stage, x 48; 19-21, opposite sides and apertural view of holotype, x 25; 22-28, diagrams showing progressive ontogenetic changes in aperture, as dissected progressively from adult (fig. 22) back to juvenile (fig. 28), showing change from juvenile simple tooth to bifid tooth to ringlike form attached in four places and leaving five openings (from Didkovsky, 1957). courtesy of Michael Hesemann https://foraminifera.eu