| Species | Psiloceras superius WÄHNER |
| Author | WÄHNER |
| Group | Psiloceraten |
| Horizon | curviornatum-horizon |
| Zone | megastoma-Zone |
| Stage | Middle Hettangian |
Description
The winding cross-section is almost circular, the umbilical width very large. After a distinct nodule stage, proradiate, simple ribs set in, bending externally towards the front. The ribs are rather low and broad. With age the ribs become lower, are only slightly proradiate and bend forward almost imperceptibly near the external side.
Compare
This species is very easy to confuse with Caloceras johnstoni (Sowerby) at first sight. Characteristic for the genus Psiloceras, however, is the complicated lobe line and the nodule stage.
The ribs are lower and not as bulging as in Caloceras. P. superius differs from other Psiloceras by the very large navel width.
Dimension
Dimensions with D= 80mm:
Nw % v. D: ca. 63%
Wh % v. D: ca. 24%
Wb % v. D: ca. 20%
Literature
- 1886 Aegoceras johnstoni SOW. mut. superius n.f. – Wähner S. 148, Taf, 16.7-9
- 1952 Psiloceras (Paraphylloceras) superius Wähner – Lange, S. 126
