| Species | Megastomoceras paltar (WÄHNER) |
| Author | WÄHNER |
| Group | Psiloceraten |
| Horizon | curviornatum-horizon |
| Zone | megastoma-Zone |
| Stage | Middle Hettangian |
Description
After a distinct nodule stage, numerous and low, slightly retroradiate ribs begin, just crossing the flanks and bending forward near the external side. Most ribs die out, few cross the external side.
The cross-section of the windings is highly oval with flat flanks, but the largest winding width is measured at the umbilical edge. This means that the flanks converge towards the external side.
* Description according to Wähner (1883), supplemented
Compare
The numerous ribs and the cross-section of the coils are quite characteristic. M. paltar looks a little like a much older species: Psiloceras naumanni. However, the latter has parallel flanks and a much smaller Wb with a larger Nw.
Dimension
Dimensions with D= 100mm
Nw % v. D: ca. 52%
Wh % v. D: ca. 28%
Wb % v. D: ca. 20%
Literature
- 1883 Aegoceras Paltar n.f. – Wähner S. 121, Taf, 21.9
- 1952 Storthoceras (Megastomoceras) aff. paltar Wähner – Lange, S. 138, Taf. 18.1
