Oocerina

Oocerina
Temporal range: Silurian
Oonocerina plebeia, Barrande from Slivenec, Prague, (Czech Republic) at the National Museum (Prague)
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Oncocerida
Family: Oncoceratidae
Genus: Oocerina
Foerste, 1926

Oocerina is an extinct genus of nautiloid cephalopods that lived during the Late Silurian of Europe, Russia, and North America.

Oocerina, included in the oncoerid family Oncoceratidae and arbitrarily within the Slender Oncoceratidae, is characterized by a moderately slender, elongate shell with an exogastric curvature, such that the lower side with the siphuncle is convex in profile and the opposite, upper, side is concave in profile. Shells are laterally compressed, curvature is gentle to almost straight. Chambers are short, septa close spaced, sutures typically straight. The siphuncle is nummuloidal, containing actinosiphonate deposits within.

Oonoceras is similar except for having a generally stronger curvatue and a simpler, non-actinosiphonate siphuncle.

Oonocerina plebeia, Barrande from Slivenec, Prague, (Czech Republic) at the National Museum (Prague)

References

This article is issued from Wikipedia - version of the 10/12/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.