Clinoceratidae is an extinct family of actively mobile carnivorous cephalopod of the order Orthocerida that lived in what would be North America and Europe during the middle Ordovician through Early Silurian from 466–443.7 mya, existing for approximately .PaleoBiology Database: Clinoceratidae, basic info
Taxonomy Clinoceratidae was named by Flower (1946). Its type is Clinoceras. It was assigned to Michelinoceratida by Flower (1962).R. H. Flower. 1962. Part 1, Revision of Buttsoceras, Part 2, Notes on the Michelinoceratida. State Bureau of Mines and Mineral Resources, New Mexico Institute of Mining and Technology, Memoir 10:1-58
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.
References
Fossils (Smithsonian Handbooks) by David Ward