| Species | Discamphiceras calcimontanum (WÄHNER) |
| Author | WÄHNER |
| Group | Psiloceraten |
| Horizon | curviornatum-horizon |
| Zone | megastoma-Zone |
| Stage | Middle Hettangian |
Description
D. calcimontanum joins D. pleuronotum and D. toxophorum. It differs by the narrower navel.
After a distinct nodule stage, numerous, low ribs begin to run radially across the flanks, bending sharply forward near the external side and becoming extinguished in the process. Sometimes, in good preservation, very faint extensions of the ribs can be observed, which unite externally.
As with other discamphicerates, irregularities in the ribbing or split ribs are present.
The cross-section of the windings is highly oval, with an umbilical edge, flattened flanks and a rounded outer side.
D. calcimontanum is so far only known with medium-sized specimens.
* Description according to WÄHNER (1883), supplemented
Compare
D. calcimontanum is characterised by the rather narrow navel, the flat flanks with navel edge and the medium strong ribbing.
Confusion with species of the Storthoceras/ Megastomoceras group is not possible.
Dimension
Dimensions at D= 43mm (according to Wähner):
Nw % v. D: ca. 30%
Wh % v. D: ca. 41%
Wb % v. D: ca. 26%
Literature
- 1883 Aegoceras calcimontanum n.f. – WÄHNER S. 110, Taf. 12.5-7
