Acanthohoplites
Acanthohoplites is a Lower Cretaceous ammonite in the family Douvilleiceratidae that has a strongly ribbed shell and ammonitic suture.
Early whorls are coronate, which later become round, then oval in section. Primary ribs may have swellings (bullae) at the umbilicus or are without. In early stages primary ribs branch mid flank at prominent lateral tubercles. In later stages lateral tubercles are reduced or absent and primary ribs branch simply at the umbilical shoulder or, again, mid flank.
Sutural elements are subquadrate with narrow, shallow embayments. The first lateral lobe tends to be symmetrical.
Acanthohoplites has been found in upper Aptian and lower Albian sediments in Europe, Central Asia, Japan, East Africa, Arizona, California, Oregon Mexico, and South America.
Parahoplites and Hypacanthoplites are similar genera.
The taxonomic position here follows the classification in the Treatise Pt L, 1957. Newer classifications may have revised taxonomies.
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Tags: Аммониты, Вымершие беспозвоночные, Мел
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