Dorsanum corbiana (d’Orbigny, 1844)

Frolov, Pavel D., Danukalova, Guzel A. & Osipova, Eugenia M., 2018, Late Miocene molluscs of the Morskaya 2 site (Azov Sea region, Russia), Palaeontologia Electronica (a 20) 23 (1), pp. 1-32 : 10-11

Dorsanum corbiana (d’Orbigny, 1844)

Figure 4.7

1844 Buccinum corbianum d’Orbigny , p. 464.

1932 Buccinum corbianum d’Orbigny ; Kolesnikov, p. 103, pl. 4, figs. 1-5.

1935 Buccinum corbianum d’Orbigny ; Kolesnikov, p. 262, pl. 31, figs. 12-14.

2012 Duplicata corbiana (d’Orbigny) ; O. Anistratenko and V. Anistratenko, p. 121.

Material. 7 specimens from layer 2.

Description. Fusiform shell with a pointy apex (HS is about 19 mm; WS is about 10 mm), moderately high (WS/HS is 0.55-0.6), consisting of 6 slightly convex whorls separated by a slightly sloping surface suture. The last whorl is about 0.7-0.8 of the height of the shell (HLW/HS). Aperture is oval, pointed in the upper part (WA/HA is 0.6), and is about 0.45-0.5 of the total height of the shell (HA/ HS). The outer edge of aperture is thin; the inner one is tightly adjacent to the shell. There is a well-developed wide siphonal canal in the lower part of aperture.

The shell surface sculpture appears from the second whorl and consists of radial ribs. On the upper whorls it is clearly seen that they consist of 3 rows of tubercles connected by spiral lines (usually poorly visible). The upper row of tubercles forms a keel inflection. The surface of the whorls above the tubercles is smooth. Starting from the fourth whorl, in the suture area, an additional row of tubercles spaced apart of ribs appears. The tubercles on the ribs of the last whorl are not always distinguishable. Ribs always look uniform on the last whorl. They are slightly curved. 8-10 ribs are visible on the last whorl in the normal position of the shell. Adumbilicus is covered by coarse growth lines and is separated from the fold of the column by a shaft. Region of distribution and age. Early and Middle Sarmatian of the Central and Eastern Paratethys (O. Anistratenko and V. Anistratenko, 2012).

Figures

FIGURE 4. Assemblage of the Middle Sarmatian (Bessarabian) marine gastropods (layers 1 and 2). 1, Acteocina lajonkaireana (Basterot, 1825). 2, Acteocina okeni (Eichwald, 1850). 3, Retusa melitopolitana (Sokolov, 1899). 4, Hydrobia elongata Eichwald, 1830. 5, Pseudamnicola nympha (Eichwald, 1850). 6, Dorsanum duplicata opinabile (Kolesnikov, 1932). 7, Dorsanum corbiana (d’Orbigny, 1844). 8, Dorsanum ignobile (Kolesnikov, 1932). 9, Gibbula (Gibbula) pseudoangulata (Sinzov, 1875). 10, Gibbula (Sarmatigibbula) podolica (Du Bois de Montpéreux, 1831).