| Species | Vermiceras (Gyrophioceras) supraspiratus (WÄHNER) |
| Author | WÄHNER |
| Group | Arieten |
| Horizon | atanatense-horizon |
| Zone | marmoreum-zone |
| Stage | Upper Hettangian |
Description
The wide-billed species has rounded flanks and a strong keel with deep furrows and indicated secondary keels.
The cross-section of the coils is approximately circular in juvenile stages and becomes highly rectangular in old age. The slope of the flanks towards the navel is flat, the external side appears rather flattened.
After a distinct nodule stage, straight, radial ribs with wide spaces set in, which bend forward from a diameter of about 10mm near the external side and then merge into the secondary keels. The greatest rib height is observed on the outer half of the flank.
The species occurs together with D. atanatense and is small-bodied and rare. It is therefore stratigraphically younger than V. (G.) praespiratissimus.
* Description according to Kment (2000), supplemented
Compare
Characteristic for this species is the ribbing (with nodule stage!) in connection with the strong keel and the deep furrows on the flattened external side.
V. (G.) praespiratissimus has a smaller coil thickness and much shallower keel furrows.
Dimension
Dimensions with D= 32mm (according to Wähner):
Nw % v. D: ca. 64%
Wh % v. D: ca. 20%
Wb % v. D: ca. 25%
Literature
- 1887 Arietites supraspiratus n.f. – Wähner S. 155, Taf, 39.6-9
- 1994 Vermiceras (Gyrophioceras) supraspiuratum Wähner – Bloos, S. 10
- 2000 Vermiceras (Gyrophioceras) supraspiratum Wähner – Kment S. 207
