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Bettoniceras

Bettoniceras
Temporal range: Pliensbachian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Dactylioceratidae
Subfamily: Reynesocoeloceratinae
Genus: Bettoniceras
Wiedenmayer, 1977
Type species
Coeloceras italicum
Fucini, 1900
Species
  • B. italicum (Fucini, 1900)
  • B. inaequiornatum (Bettoni, 1900)
  • B. colubriforme (Bettoni, 1900)

Bettoniceras is genus of ammonite that lived during the Pliensbachian stage of early Jurassic. It evolved from Reynesocoeloceras in Davoei ammonite zone and died out during Margaritatus zone. It is possible that Prodactylioceras evolved from this genus. Fossils of this genus have been found in Europe, Morocco, Tunisia, and Chile. Sometimes this genus is not considered valid, but just as a synonym of Prodactylioceras.

Ammonites of this genus had serpenticone planulate shells with mostly single ribs and no tubercules. Whorl section was round. Only difference between Prodactylioceras and Bettoniceras is that latter is missing tubercules.


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Wikipedia

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