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Cheltonia

Cheltonia
Temporal range: Sinemurian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Superfamily: Psiloceratoidea
Family: Oxynoticeratidae
Genus: Cheltonia
Buckman 1904
Type species
Ammonites accipitris Buckman, 1844
Species
  • Ch. accipitris Buckman, 1844
  • Ch. galeata Hoffmann, 1944
  • Ch. oustense Rakús & Guex, 2002

Cheltonia is an extinct genus of ammonite from the Upper Sinemurian substage of Lower Jurassic of Europe, Africa, and America. It is probably a microconch of genus Oxynoticeras.

Ammonites belonging to this genus had small platyconic shell, on which the last whorl has been eccentrically coiled. Ventral rostrum could be preceded by 3 to 5 crawlings. Umbilicus took about 30—40% of diameter. Ribs were falcoid and weak. Suture has been the same as in the case of young Oxynoticeras.


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Wikipedia

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