Cryptoplocus subpyramidalis ( Muenster in Goldfuss, 1844)

Gruendel, Joachim, Keupp, Helmut, Lang, Fritz & Nuetzel, Alexander, 2022, Late Jurassic (Upper Kimmeridgian) Heterobranchia (Gastropoda) of the coral-facies of Saal near Kelheim and the viciniy of Nattheim (Germany), Zitteliana 96, pp. 179-221 : 179

Cryptoplocus subpyramidalis ( Muenster in Goldfuss, 1844)

Plate 14: fig. 6

1844 - Nerinea subpyramidalis Münster - Münster in Goldfuss: 40, pl. 175, fig. 7.

1882 - Cryptoplocus subpyramidalis Münster - Schlosser: 86, pl. 12, fig. 10.

?1931 - Cryptoplocus pyramidalis Münster - Yin: 66, pl. 7, figs 11-15.

1931 - Cryptoplocus subpyramidalis Münster - Yin: 67, pl. 8, fig. 1.

Material.

Three specimens from Saal: two specimens collection Lang, one of which is illustrated (SNSB-BSPG 2021 XV 61), one specimen collection Keupp: SNSB-BSPG 2021 XV 62).

Description.

The larger specimen (composed of numerous fragments) is incomplete and is 103 mm high. The shell is conical with regularly increasing whorls. The whorls are very low in relation to their height. The whorl face is weakly concave. A weak subsutural bulge with narrow ramp accentuates the sutures. No ornament is visible on the whorls. The base is moderately convex. The transition from base to whorl face forms a distinct edge. No other morphological details are preserved.

Relationships.

Cryptoplocus pyramidalis ( Münster in Goldfuss) sensu Yin (1931) and Trochalia subpyramidalis Sharpe sensu Loriol in Loriol and Pellat (1874) lack a subsutural bulge. Nerinea pyramidalis Münster in Goldfuss, 1844 has a distinctly concave whorl face. In Trochalia engeli Geiger sensu Geiger (1901) and Hägele (1997), Nerinea pyramidalis sensu Quenstedt (1881-1884), Peters (1855), Gemmellaro (1870), and Münster in Goldfuss (1844) the bulge is situated above the suture (not subsutural).

Figures

Plate 14. (1 - 5) Cryptoplocus depressus (Voltz, 1836). (1 - 2) Collection Sauerborn, Nattheim area; (1) l ateral view, height 78 mm; (2) base, width 29 mm. (3 - 4) University Tuebingen (collection Quenstedt), Nattheim; (3) lateral view, height 37 mm; (4) last whorls with aperture, width 25 mm. (5) SNSB-BSPG XV 106, Saal (collection Lang), columellar section, height 47 mm. (6) Cryptoplocus subpyramidalis (Muenster in Goldfuss, 1844), SNSB-BSPG 2021 XV 61, Saal (collection Lang), lateral view, height 103 mm.