Dumortieria Explained

Dumortieria is a genus of ammonites belonging to the family Graphoceratidae.[1]

Fossil record

These cephalopods were fast-moving nektonic carnivores. They lived in the Early Jurassic, upper Toarcian age (from about 180.1 to 175.6 million years ago). Fossils of species within this genus can be found in Bulgaria, Canada, France, Germany, Hungary, Iran, Italy, Spain and Tunisia.

Description

Dumortiera are rather similar to Grammoceras and Catulloceras from the same age, having a thin, discoidally evolute shell with simple, gently sigmoid ribbing and a low ventral keel, but this species has a les rounded venter and Catulloceras has a subquadrate whorl section.[2]

Species

Species within this genus include:[3]

See also

Notes and References

  1. https://www.mv.helsinki.fi/home/mhaaramo/metazoa/protostoma/mollusca/cephalopoda/ammonoidea/ammonitida.html Mikko's Phylogeny Archive
  2. http://strata.geology.wisc.edu/jack/showgenera.php?taxon=231&rank=class Sepkoski Online
  3. http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=14800# Fossilworks