Megasphaeroceras

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Megasphaeroceras
Temporal range: Bajocian [1]
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Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Family: Sphaeroceratidae
Genus:Megasphaeroceras

Megasphaeroceras is an ammonite genus included in Sphaeroceratidae, a family of ammonoid [2] cephalopods characterized by their sphaeroidal shells with markedly eccentric coiling, fine ribbing, and complex sutures, known from the Bajocian. [1]

In the geologic timescale, the Bajocian is an age and stage in the Middle Jurassic. It lasted from approximately 170.3 Ma to around 168.3 Ma. The Bajocian age succeeds the Aalenian age and precedes the Bathonian age.

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References

Notes
  1. 1 2 Sepkoski, Jack (2002). "A compendium of fossil marine animal genera (Cephalopoda entry)". Bulletins of American Paleontology. 363: 1–560. Archived from the original on 2008-05-07. Retrieved 2017-10-18.
  2. "Paleobiology Database - Megasphaeroceras" . Retrieved 2017-10-19.
Bibliography