Acanthohoplites
Encyclopedia
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.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
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
Aptian
The Aptian is an age in the geologic timescale or a stage in the stratigraphic column. It is a subdivision of the Early or Lower Cretaceous epoch or series and encompasses the time from 125.0 ± 1.0 Ma to 112.0 ± 1.0 Ma , approximately...
and lower Albian
Albian
The Albian is both an age of the geologic timescale and a stage in the stratigraphic column. It is the youngest or uppermost subdivision of the Early/Lower Cretaceous epoch/series. Its approximate time range is 112.0 ± 1.0 Ma to 99.6 ± 0.9 Ma...
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
Treatise on Invertebrate Paleontology
The Treatise on Invertebrate Paleontology published by the Geological Society of America and the University of Kansas Press, is a definitive multi-authored work of some 50 volumes, written by more than 300 paleontologists, and covering every phylum, class, order, family, and genus of fossil and...
Pt L, 1957. Newer classifications may have revised taxonomies.
References
- Arkell,et al, Mesozoic Ammonoidea; Treatise on Invertebrate Paleontology, Part L, Ammonoidea. Geol Soc of America and Univ Kansas press, 1957. R.C. Moore (ed)
- Paleobiology DB Acanthohoplites