Heteroceras is a genus of Lower Cretaceous heteromorph ammonites belonging to the ancyloceratoidean family, Heteroceratidae.[1]

Heteroceras
Temporal range: Barremian–Aptian
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Suborder: Ancyloceratina
Family: Heteroceratidae
Genus: Heteroceras
d'Orbigny, 1849

Description

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It is characterized by a helically coiled juvenile shell at the apex followed by slightly curved adult shaft, with a J-shaped section at the end of it. The shell is ribbed; ribs are concave and oblique on the helix, straight and transverse on the later stages.

Distribution

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Heteroceras has been found in Argentina, Bulgaria, Colombia (La Guajira), the Czech Republic, France, Italy, Japan, Madagascar, Serbia and Montenegro, South Africa, Spain, Russia and the United States (Kansas, Wyoming).[2] Related genera are Hemibaculites and Cochidites. The family, Heteroceratidae, is a derivative of the Ancyloceratidae.

References

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  1. ^ Wright, C. W. with Callomon, J.H. and Howarth, M.K. (1996), Mollusca 4 Revised , Cretaceous Ammonoidea, vol. 4, in Treatise on Invertebrate Paleontology, Part L (Roger L. Kaesler ed.), Boulder, Colorado: The Geological Society of America & Lawrence, Kansas: University of Kansas Press, p. 227.
  2. ^ "Heteroceras". Fossilworks. Retrieved 15 June 2022.

Further reading

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