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 edit

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 edit

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 edit

  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 edit