Axonoceras

Axonoceras is a genus in the ammonitid family Nostoceratidae proposed by Stephenson in 1941,[2] for "slender shells coiled in a plane with numerous closely spaced ribs and two rows of ventral nodes'...The shells may be closely coiled, though not involute, but most... are more or less loosely and irregularly coiled". Shells may be coplanar or coiled in a low flat spiral with the early whorls in contact, later whorls free.

Axonoceras Temporal range: Campanian–Maastrichtian[1] PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Ammonoidea
Order:	Ammonitida
Family:	Nostoceratidae
Genus:	Axonoceras Stephenson, 1941
species
see text

Axonoceras comes from the Campanian of Texas and New Jersey in the United States and Angola in west Aftrica. The type species is Axonoceras compressum Stephenson 1941.[3]

Axonoceras and Exiteloceras are similar with Axonoceras sometimes considered a subjective synonym of Exiteloceras. The adult of Axonoceras however is very small. Exiteloceras is much larger

References

Notes

1. Sepkoski, Jack (2002). "Sepkoski's Online Genus Database". Retrieved 2014-05-28.
2. "Geological Survey Professional Paper". Cite journal requires |journal= (help)
3. "Index of Scientific Names". Cite journal requires |journal= (help)

Bibliography

• Ammonites from the Navesink Formation at Atlantic Highlands, New Jersey; by William A Cobban 1974, USGS Prof Paper 845.
• 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.