Paroxynoticeras

Paroxynoticeras is an extinct genus of lower Jurassic ammonite that lived during upper Sinemurian. Animals belonging to this genus had platyconic shells with compressed whorl section and could grow to large sizes. In the case of young specimens, umbilicum is small, but it increases in bigger specimens.. Last whorl is excentric, which can occur also in relative species, Paracymbites. While on the outer whorls, venter is always rounded, on inner whorls it can be both rounded or sharp. Ornamentation on inner whorls and suture is similar to Oxynoticeras, but in bigger specimens, ribs became straight, simple and blunt. In these bigger specimens, midlateral tubercules might be present.[1]

Paroxynoticeras
Temporal range:
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Subclass: †Ammonoidea
Order: †Ammonitida
Family: †Oxynoticeratidae
Genus: †Paroxynoticeras
Pia, 1914
Type species
Ammonites salisburgensis
Hauer, 1856
Species
  • Paroxynoticeras salisburgense Hauer, 1856
  • Paroxynoticeras subundulatum Pia, 1914
Synonyms
  • Paraoxynoticeras Arkell, 1957

Distribution

Fossils belonging to this genus were found in Europe, Tunisia and Morocco.[1]

References
  1. M. K. Howarth 2013. Treatise on Invertebrate Paleontology, Part L, Revised, Volume 3B, Chapter 4: Psiloceratoidea, Eoderoceratoidea, Hildoceratoidea.


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