Paradnatoceras is an extinct straight-shelled cephalopod genus that lived in what would become China during the Ordovician from 478.6 to about 461 mya, existing for approximately 17.6 Ma.PaleoBiology Database: Paradnatoceras, basic info
Taxonomy Paradnatoceras is included in the Orthocerida according to Sepkoski (2002).J. J. Sepkoski. 2002. A compendium of fossil marine animal genera. Bulletins of American Paleontology 363:1-560 Inclusion of the Orthocerida in the subclass Orthoceratoidea is according to more recent taxonomic opinion.Björn Kröger. A new genus of middle Tremadocian orthoceratoids and the Early Ordovician origin of orthoceratoid cephalopods. Acta Palaeontologica Polonica 53 (4): 745–749, 2008 In older taxonomies, e.g.,Treatise on Invertebrate Paleontology, Part K, 1964; Teichert and Moore (eds) the Orthocerida were included in the Nautiloidea.
Morphology The shell is usually long, and may be straight ("orthoconic") or gently curved. In life, these animals may have been similar to the modern squid, except for the long shell.
Fossil distribution Fossil distribution is exclusive to central and southern China.
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