Astiericeras
| Astiericeras Temporal range: Albian[1] | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Cephalopoda |
| Subclass: | Ammonoidea |
| Order: | Ammonitida |
| Superfamily: | Ancylocerataceae (?) |
| Family: | Douvilleiceratidae |
| Subfamily: | Douvilleiceratinae |
| Genus: | Astiericeras Parona & Bonarelli. 1896 |
| Species | |
| |
Astiericeras is an ammonite from the Lower Cretaceous, the shell of which is evolute, stout; outer whorl with strong, well spaced, transverse ribs that cross smoothly over the broad venter; early whorls with lateral tubercles. The outer, mature whorl separates from the coil but hooks back quickly, referred to as a heteromorph.
Astiericeras is generally considered to be a douvillieceratid,[2] however according to W. J. Kennedy, the genus may instead be a scaphitoid.[3]
References
- ↑ Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
- ↑ Arkell, W.J.; Kummel, B.; Wright, C.W. (1957). Mesozoic Ammonoidea. Treatise on Invertebrate Paleontology, Part L, Mollusca 4. Lawrence, Kansas: Geological Society of America and University of Kansas Press.
- ↑ Kennedy, W. J. (1985). "Observations on Astiericeras astierianum (d'Orbigny, 1842) (Cretaceous Ammonoidea)". Geological Magazine 123 (5): 507–513. doi:10.1017/S0016756800035093.
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