Astiericeras

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
Temporal range:
Scientific classification
Kingdom:
Animalia
Phylum:
Mollusca
Class:
Cephalopoda
Subclass:
Ammonoidea
Order:
Ammonitida
Superfamily:
Ancylocerataceae (?)
Family:
Douvilleiceratidae
Subfamily:
Douvilleiceratinae
Genus:
Astiericeras

Parona & Bonarelli. 1896
Species
  • see text

Astiericeras is generally considered to be a douvillieceratid.[2] However, according to W. J. Kennedy, the genus may instead be a scaphitoid.[3]

References
  1. Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
  2. 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.
  3. 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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