Phaedrysmocheilus

Phaedrysmocheilus
Temporal range: Early Triassic
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Nautiloidea
Order: Nautilida
Genus: Phaedrysmocheilus
Shimanskiy & Erlanger, 1955

Phaedrysmocheilus is an Early Triassic Tainoceratid genus (Nautiloidea, Cephalopoda) from Siberia. The shell is a rapidly expanding, moderately involute nautilicone; smooth in the adult stage but laterally ribbed in the juvenile stage. Volutions are convex laterally, arched ventrally, embraced dorsally. Whorl sections change during development from being slightly depressed, early, to slightly compressed later, changing from being relatively wide to relatively high. The umbilicus is deep and funnel shaped. Sutures are slightly sinuous.

References

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