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Cetonoceras

Cetonoceras
Temporal range: Pliensbachian
Scientific classification
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: Ammonoidea
Order: Ammonitida
Family: Dactylioceratidae
Subfamily: Reynesocoeloceratinae
Genus: Cetonoceras
Wiedenmayer, 1977
Type species
Coeloceras psiloceroides
Fucini, 1905
Species
  • C. psiloceroides Fucini, 1905
Synonyms
  • Seccianoceras Venturi in Faraoni et al., 1995

Cetonoceras is genus of ammonite that lived during the upper Pliensbachian stage of early Jurassic. Fossils of this genus were found in Italy, France, Spain, Portugal, Hungary and Austria.

First whorls of shell are depressed, but then they became rounded and more compressed. Primary ribs are strong and they are usually bifurcating. Secondary ribs are more delicate. Tubercules are present on ventrolateral positions in younger whorls, but they are diminishing on outer whorls. Similar genus is Reynesocoeloceras, but that one is lacking ribs bifurcations.



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