| Species | Storthoceras curviornatum WÄHNER |
| Author | WÄHNER |
| Group | Psiloceraten |
| Horizon | curviornatum-horizon |
| Zone | megastoma-Zone |
| Stage | Middle Hettangian |
Description
After a distinct nodule stage, the strong and high ribs begin, bending strongly forward near the external side and crossing it in young specimens. They become weaker with age and end quite far in front of the external side. The forward bend may almost no longer be visible.
The winding cross-section is oval, the outer side broadly rounded. The species grows quite large.
* Description according to Wähner (1882), supplemented
Compare
Small specimens are similar to Storthoceras extracostatum. However, this has a larger Nw and higher, more numerous ribs.
The very long, clearly observable ribs clearly point to Storthoceras, nevertheless, with very large specimens there is the danger of confusion with species from the megastoma group, because the sculpture is strongly weakened. Here, the decisive distinguishing feature is the much more complicated lobe line in megastomoceras.
Dimension
Dimensions with D= 60mm
Nw % v. D: ca. 40%
Wh % v. D: ca. 34%
Wb % v. D: ca. 23%
Literature
- 1882 Aegoceras curviornatum n.f. – Wähner S. 75, Taf. 16.2-4
- 1952 Storthoceras curviornatum Wähner – Lange, S. 131.5
