*** Welcome to piglix ***

Mcqueenoceras

Mcqueenoceras
Temporal range: Ordovician
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Endocerida
Family: Proterocameroceratidae
Genus: Mcqueenoceras

Mcqueenoceras is an exxtinct genus of early endocerid, a nautilus from the Ordovician period similar in overall form to Clitendoceras, from which it may have been derived. It lived during the later stages of the lower Ordovician. McQueenoceras, like Clitendoceras, has ventral siphuncle but the endocones are thicker on the ventral side and thinner on the dorsal. Also the sutures in McQueenoceras retreat rearward, forming lobes as they cross the venter.


...
Wikipedia

...