| Species | Waehneroceras minor (Blind) |
| Author | BLIND |
| Group | Psiloceraten |
| Horizon | calliphyllum-horizon strongolum-horizon |
| Zone | calliphyllum-zone tilmanni-zone |
| Stage | Lower Hettangian |
Description
The species is small in size and the cross-section of the coils is oval. The innermost coils are more evolute than the outer ones. The umbilical edge is rounded, the umbilical slope steep. The flank is slightly convex, often flattened on the outermost turn.
No clear nodule stage can be observed. After a smooth innermost turn, little raised nodules set in. They are small and can also be described as flat, broad ribs.
These first ribs merge into slender, low ribs that stand radiate to slightly proradiate. They start at the umbilical edge, cross the flank and then bend forward and cross the external side. On the following coils the ribs become increasingly s-shaped and irregular:
The height varies, as does the spacing of the ribs; low intermediate ribs may occur.
In adult specimens the sculpture on the living chamber is strongly weakened. Only accretion stripes may still be present.
* Description according to Kment (2021), supplemented
Compare
At the level where this species occurs, it is unmistakable. The S-shaped, irregular ribs are characteristic. Very similar are younger forms like Storthoceras frigga, as Blind already noted in 1963.
Dimension
Dimensions with D = 18mm
Nw % v. D: 37%
Wh % v. D: 38%
Wb % v. D: 35%
Literature
- 1963 Psiloceras (Storthoceras) frigga minor n. subspec. – BLIND, p. 55. pl. 1, fig. 8.
- 2021 Waehneroceras minor (Blind). – KMENT, S. 256, Abb. 5.10-11, 13.1
