• Source: Crioceratites
  • Crioceratites is an ammonite genus from the Early Cretaceous belonging to the Ancyloceratoidea.
    Crioceratites was formerly included in the Ancyloceratidae, in the subfamily Crioceratinae which was subsequently elevated in rank to the family Crioceratidae. Crioceras and Toxoceras d'Orbigny and possibly Emericiceras Sarka 1954 are junior synonyms.


    Species


    Species within the genus Crioceratites include:


    Description


    Crioceratites is coiled in an open, normally equiangular spiral with an oval or subquadrate whorl section. The surface is banded by fine, dense, rounded ribbing sectioned by periodically spaced thick and often spinose ribs.


    Distribution


    Crioceratites fossils have been found in Lower Cretaceous Valanginian-Barremanian, sediments in Europe, Africa, Asia, North America and South America; Argentina, Chile and Colombia (Paja Formation).


    References




    Further reading


    Simon & Schuster's Guide To Fossils (Nature Guide Series) by Paolo Arduini
    Treatise on Invertebrate Paleontology, Part L, Ammonoidea,--Ancyloceratiaceae; Geological Society of America 1957, reprinted 1990.

Kata Kunci Pencarian: