''Cetonoceras'' is genus of

ammonite Ammonoids are a group of extinct marine mollusc animals in the subclass Ammonoidea of the class Cephalopoda. These molluscs, commonly referred to as ammonites, are more closely related to living coleoids (i.e., octopuses, squid and cuttlefish) ...

that lived during the upper Pliensbachian stage of early Jurassic. Fossils of this genus were found in Italy, France, Spain, Portugal, Hungary and Austria.Géczy, B., Meister, C. 1998. Les ammonites du Domérien de la montagne du Bakony (Hongrie). Revue de Paléobiologie 17(1):69-161

Description

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 ''Reynesocoeloceras'' is genus of ammonite that lived during the lower Pliensbachian stage of early Jurassic The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) ...

'', but that one is lacking ribs bifurcations.Blau, J., Meister C. (1991). Liassic (Pliensbachian) Ammonites from the Lienz Dolomites (Eastern Tyrol, Austria).

References

Dactylioceratidae Pliensbachian life Early Jurassic ammonites of Europe Ammonite genera {{Ammonitina-stub