Acrioceras is an extinct genus of cephalopods belonging to the ammonite subclass. with and (1996), Mollusca 4 Revised, Cretaceous Ammonoidea, vol. 4, in Treatise on Invertebrate Paleontology, Part L (Roger L. Kaesler ed.), Boulder, Colorado: The Geological Society of America & Lawrence, Kansas: University of Kansas Press, pp. 223, 224.
Description A spire of one or two loosely coiled whorls followed by a short or long, straight or curved shaft, terminal hook, and short and or long final shaft. The ribs are generally fine and untuberculate, but sometimes the major ribs are enlarged and are carrying one to three tubercles. The ribs are single on the spire or the shaft but may branch from umbilical tubercles on the hook and the final shaft. The dorsum tends to become flat and the dorsolateral margin to become angular on the shaft and the hook.
Distribution Fossils of Acrioceras have been found in: Barremian Formation, Brestak, Bulgaria Ono Formation, California Paja Formation, Colombia Barremian Provence, France Georgia Subway Formation, Germany Maiolica Formation, Italy Ishido and Inagoe Formations, Japan San Lucas Formation, Mexico Taboulouart Formation, Morocco Hauterivian, Slovakia Makatini Formation, South Africa Hauterivian Murcia, Spain
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