Aspidostephanus
Appearance
Aspidostephanus Temporal range:
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Subfamily: | Spiticeratinae
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Genus: | Aspidostephanus Spath, 1925
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Aspidostephanus is an extinct cephalopod genus belonging to the ammonite subclass, included in the perisphinctacean family Olcostephanidae that lived during the earliest Cretaceous and possible latest Jurassic. Fossils of the genus have been found in France, the Balearics, North Africa, and Argentina.
The shell of Aspidostephanus is depressed with a broad smooth venter. Early whorls have strong lateral ribs with umbilical and lateral tubercles; later whorls smooth except for tubercles at the umbilicus. Whorl height increases with age. Aspidostephanus is similar to but broader than its close relative, Spiticeras.
References
[edit]- ^ Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2016-02-25. Retrieved 2017-10-18.
- 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.