Echioceratidae is an extinct family of ammonites that lived during Sinemurian stage of Early Jurassic.
Description Ammonites belonging to this family are characterised by serpenticone shells with a keel, which can be surrounded by grooves if a species is densely ribbed and compressed. The whorl section is either circular or has flat sides. Ribs are simple and strong with the exception of Leptechioceras which instead possessed a strongly compressed, smooth outer whorl. The initial ontogenical stage of these ammonites is typically smooth but very short. Tubercules are represented in a few genera within this group.M. K. Howarth 2013. Treatise on Invertebrate Paleontology, Part L, Revised, Volume 3B, Chapter 4: Psiloceratoidea, Eoderoceratoidea, Hildoceratoidea.
Genera and subgenera Following genera are members of this family:
Palaeoechioceras Spath, 1929 Gagaticeras Buckman, 1913 Plesechioceras Trueman and Williams, 1925 Orthechioceras Trueman and Williams, 1925 Echioceras Bayle, 1878 Paltechioceras Buckman, 1924 Leptechioceras Buckman, 1923 L. (Leptechioceras) L. (Neomicroceras) Donovan, 1966
Distribution Fossils of species within this family have been found in the Jurassic rocks of north Africa, South and North America, Europe and Asia.
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