• Source: Acrioceras
  • Acrioceras is an extinct genus of cephalopods belonging to the ammonite subclass.


    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


    References




    External links


    Wright, Claud William; with John Hannes Callomon and M.K. Howarth (1996). Roger L. Kaesler (ed.). Mollusca 4 Revised, Cretaceous Ammonoidea in Treatise on Invertebrate Paleontology Part L. Boulder, Colorado and Lawrence, Kansas: The Geological Society of America & University of Kansas Press. p. 223-224.{{cite book}}: CS1 maint: multiple names: authors list (link)
    "Acrioceras". mindat.org. Retrieved 11 February 2024.
    "Acrioceras". PaleoBioDB (PBDB). Retrieved 11 February 2024.

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