Orthoceratidae
{{Short description|Extinct family of molluscs}}
{{Automatic taxobox
| fossil_range = Ordovician - Permian (possibly Triassic)
| image = Orthoceras BW.jpg
| image_caption = Orthoceras
| taxon = Orthoceratidae
| authority = McCoy, 1844
| subdivision_ranks = Genera
| subdivision =
- †Bitaunioceras
- †Chebbioceras
- †Ctenoceras
- †Infundibuloceras
- †Kionoceras
- †Kopaninoceras
- †Merocycloceras
- †Michelinoceras
- †Ogygoceras
- †Orthoceras
- †Orthocycloceras
- †Oxfordoceras
- †Palorthoceras
- †Plagiostomoceras
- †Pleurorthoceras
- †Pojetoceras
- †Polygrammoceras
- †Pseudospyroceras
- †Striatocycloceras
- †Theoceras
- †Tibichoanoceras
- †Trematoceras
| synonyms = Orthocerotidae
}}
Orthoceratidae, from Ancient Greek ὀρθός (orthós), meaning "straight", and κέρας (kéras), meaning "horn", is an extinct family of actively mobile carnivorous cephalopods, subclass Nautiloidea, that lived in what would be North America, Europe, Asia, Africa, and Australia from the Ordovician through Triassic from 490—203.7 mya, existing for approximately {{Mya|490-203.6|million years}}.[https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=114117 PaleoBiology Database: Orthoceratidae, basic info]
Taxonomy
Orthoceratidae was named by McCoy (1844) and assigned to the Orthocerida by Teichert and Miller (1939),(as Orthocerotidae);Sweet, Walter C., (1964), Nautiloidea --Orthocerida, in Treatise on Invertebrate Paleontology. Part K. Mollusca 3. pp K224-K231. to the Michelinoceratida by Flower (1962),R. H. Flower. 1962. Memoir 10, Part 2; Notes on the Michelinoceratida. New Mexico Bureau of Mines and Mineral Resources, Socorro NM. and to the Orthocerataceae by Sweet (1964). It has been subsequently included in the Orthocerataceae in Evans (1994) and in the Orthocerida in Evans (2005)D. H. Evans. 2005. The Lower and Middle Ordovician cephalopod faunas of England and Wales. Monograph of the Palaeontographical Society 623:1-81 and in Kröger et al. (2007).B. Kröger, M. S. Beresi, and E. Landing. 2007. Early orthoceratoid cephalopods from the Argentine Precordillera (Lower-Middle Ordovician). Journal of Paleontology 81(6):1266-1283 Flower showed in 1962 that Orthocerotidae used by Teichert and Miller (1939) is synonymous with Orthoceratide McCoy (1884).
Morphology
Members are characterised by long, slender, usually orthoconic (straight) but sometimes slightly curved shells, a central or subcentral orthochoanitic siphuncle that is free of deposits, a long body chamber, and cylindrical or only slightly inflated connecting rings. Ornamentation may be in the form of longitudinal or transverse ribs and/or lirae, or the shell surface may be smooth.
References
{{Reflist|3}}
- Dzik, Jerzy (1984) Phylogeny of the Nautiloidea, Palaeontologica Polonica, no. 43
{{fossil cephalopods}}
{{Taxonbar|from=Q7104416}}
Category:Prehistoric cephalopod families