| Species | Alpinoceras seebachi NEUMAYR |
| Author | NEUMAYR |
| Group | Alsatiten/Alpinoceraten |
| Horizon | seebachi-horizon |
| Zone | megastoma-Zone |
| Stage | Middle Hettangian |
Description
The shells are evolute and the WQ is oval. The external side has a broad, raised keel with indistinct furrows. The keel is absent in very small specimens, where the external side is evenly rounded.
The ribbing begins on the innermost coils as nodes, which passes into a stage of strong, radial ribs. They start at the suture, run straight and predominantly radial over the flank and die out close to the external side. Occasionally, a very weak forward bend can be observed beforehand. The ribs reach their greatest height on the middle of the flank. This regular sculpture can be followed into old age.
* Description according to Wähner (1885), supplemented
Compare
Similar to Alpinoceras seebachi are A. spiratus, A. perspiratus and A. loki.
Alpinoceras spiratus has less strong and slightly curved ribs and no keel furrows.
Alpinoceras perspiratus has a thicker winding cross-section and ribs that are strongly bent forward externally.
Alpinoceras loki has a thicker coil cross-section, a wider keel and a smaller navel width.
In unfavourable preservation, delimitation is often difficult.
Dimension
Dimensions with D= 50mm (according to Wähner):
Nw % v. D: ca. 63%
Wh % v. D: ca. 18%
Wb % v. D: ca. 21%
Literature
- 1879 Arietites Seebachi n.f. – Neumayr S. 39, Taf. 2.1
- 1885 Arietites Seebachi Neum. – Wähner S. 135, Taf, 35.1 & 3
- 2000 Alpinoceras seebachi Neumayr – Kment S. 204
