Trematoceras

Trematoceras; Temporal range: U Triassic
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Subclass:	Nautiloidea
Order:	Orthocerida
Superfamily:	Orthocerataceae
Family:	Orthoceratidae
Subfamily:	Michelinoceratinae
Genus:	Trematoceras; Eichwald, 1851

Trematoceras is an orthoconic nautiloid cephalopod from the Upper Triassic of Europe and Asia named by Eichwald in 1851.

Taxonomy

Trematoceras is included in the Michelinoceratinae, a subfamily of the Orthoceratidae^[1]

Morphology

Trematoceras has a slender, subcylindrical shell with a bluntly pointed apex, long chambers, straight transverse sutures, and a smooth or faintly cancellated surface. The siphuncle is central, tubular, and empty; septal necks short, orthochoanitic; connecting rings cylindrical or only faintly expanded. Chambers contain prominent lamellar mural and episeptal deposits.^[1]

Distribution

Trematoceras has been found in Upper Triassic sediments in Afghanistan, Kazakhstan, and the Russian Federation.^[2]

References

^ ^a ^b Sweet, W.C. 1964. Nautiloidea- Orthocerida. Treatise on Invertebrate Paleontology, Part K. Geol. Soc. of America and Univ Kansas Press
^ Trematoceras -Paleobio db

[Sweet-1] Sweet, W.C. 1964. Nautiloidea- Orthocerida. Treatise on Invertebrate Paleontology, Part K. Geol. Soc. of America and Univ Kansas Press

[2] Trematoceras -Paleobio db

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