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Trematoceras

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Trematoceras
Temporal range: U Triassic
Scientific classification
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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

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

Morphology

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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

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

References

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