Astiericeras

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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
  • see text

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[edit]

  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.