Fig. 11 in Early ontogeny and palaeoecology of the Mid-Miocene rissoid gastropods of the Central Paratethys

Fig. 11. Four species of Mohrensternia Stoliczka, 1868. A. Mohrensternia pseudoangulata politioanei Jekelius, 1944. Specimen (NHMW 2002z0029/ 0009) from the Early Sarmatian of Waldhof, Styria/Austria (A1). Protoconch of the same specimen in lateral view (A2). The onset of the teleoconch is indicated by the formation of weak axial folds, grading into axial ribs. B. Mohrensternia soceni Jekelius, 1944. Specimen (NHMW 2002z0029/0012) from the Early Sarmatian of Hollabrunn (B1). Protoconch of the same specimen as in B1 in lateral view (B2). The onset of the teleoconch is indicated by the formation of axial folds. Detailed apical view of the initial whorl of the same protoconch as in B2 (B3). The embryonic shell is demarcated from the subsequent larval shell by a slightly thickened rim followed by an incision of the shell. C. Mohrensternia pfaffstaettensis sp. nov. Holotype (NHMW 2002z0029/0014) from the Early Sarmatian of Pfaffstätten, Vienna Basin/Lower Austria (C1). Lateral and apical view of the protoconch of the same specimen as in C1 (C2, C3). The protoconch is terminated by a slightly sinuous rim. The onset of the teleoconch is indicated by the formation of strong axial ribs and subordinated spiral threads. Detailed view of the initial whorl of the same protoconch as in C3 (C4). The embryonic shell has a finely granulated spiral sculpture. It is terminated by a slightly sinuous rim. D. Mohrensternia waldhofensis sp. nov. Holotype (NHMW 2002z0029/0004) from the Early Sarmatian of Waldhof, Styria/Austria (D1). Lateral and apical view of the protoconch of the same specimen (D2, D3). The transition to the teleoconch is indicated by a thickened rim which is not projecting.