Pachyceras
Pachyceras Temporal range: late Middle Jurassic (Callovian) | |
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Fossil of Pachyceras lalandeanum from Calvados (France), on display at Galerie de paléontologie et d'anatomie comparée in Paris | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Mollusca |
Class: | Cephalopoda |
Subclass: | Ammonoidea |
Order: | Ammonitida |
Superfamily: | Perisphinctaceae |
Family: | Pachyceratidae |
Genus: | Pachyceras Bayle 1878 |
Pachyceras is a perisphinctoid ammonite genus from the Middle Jurassic, upper Callovian stage, and is the type genus for the family Pachyceratidae. The shell is involute, subglobular, with a deep umbilicus and flattened flanks that slope toward a more narrowly rounded venter, and covered by low, widely spaced ribs.
References
- D. T. Donovan, J. H. Callomon and M. K. Howarth 1981. Classification of the Jurassic Ammonitina; The Ammonoidea. The Systematics Association special volume no. 18