Hesperoceras

Hesperoceras is an orthocerid cephalopod belonging to the subfamily Michelinoceratinae which comes from the lower Mississippian of New Mexico.

Hesperoceras Temporal range: L Mississippian
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Nautiloidea
Order:	Orthocerida
Superfamily:	Orthocerataceae
Family:	Orthoceratidae
Subfamily:	Michelinoceratinae
Genus:	Hesperoceras Miller & Youngquist, 1947

Hesperoceras has a straight, orthoconic, shell with a subrectangular cross section. The sutures are straight and transverse on the narrow sides but form broad rounded lobes on the wide sides, and the siphuncle is small and central.

References

• Miller, A.K. and Youngquist, W. (1947). The discovery and significance of a cephalopod fauna in the Mississippian Caballero Formation of New Mexico. Journal of Paleontology 21(2):113-117. JSTOR 1299455
• Sweet, Walter C. (1964). Nautiloidea-Orthocerida. Treatise on Invertebrate Paleontology, Part K. Geological Soc of America, and Univ Kansas Press.