Acanthohoplites


Acanthohoplites is an extinct genus of ammonites in the family Parahoplitidae that lived in the Aptian and Early Albian stages of the Early Cretaceous.

Taxonomy

The taxonomic position in the Treatise on Invertebrate Paleontology Pt L, 1957 placed the genus into the family Deshayesitidae. Newer classifications have revised that placement and the genus is now included into the family Parahoplitidae. Parahoplites and Hypacanthoplites are similar genera.

Description

These ammonites have a strongly ribbed shell and ammonitic suture. Early whorls are coronate, which later become round, then oval in section. Primary ribs may have swellings 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.

Species

The following species have been described, either as Acanthoplites or Acanthohoplites.
The species A. nolani was described as Hoplites nolani and later designated the type species of the genus Nolaniceras in 1961, and was subsequently renamed as Nolaniceras nolani.

Distribution

Acanthohoplites has been found in Upper Aptian and Lower Albian sediments in Europe, Central Asia, East Africa, North and South America: