Misplaced Pages

Orthoceratidae Temporal range: Ordovician - Permian (possibly Triassic)
Orthoceras
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Cephalopoda
Order:	†Orthocerida
Family:	†Orthoceratidae McCoy, 1844
Genera
†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 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 286.4 million years.

Taxonomy

Orthoceratidae was named by McCoy (1844) and assigned to the Orthocerida by Teichert and Miller (1939),(as Orthocerotidae); to the Michelinoceratida by Flower (1962), 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) and in Kröger et al. (2007). 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

1. PaleoBiology Database: Orthoceratidae, basic info
2. ^ Sweet, Walter C., (1964), Nautiloidea --Orthocerida, in Treatise on Invertebrate Paleontology. Part K. Mollusca 3. pp K224-K231.
3. ^ R. H. Flower. 1962. Memoir 10, Part 2; Notes on the Michelinoceratida. New Mexico Bureau of Mines and Mineral Resources, Socorro NM.
4. D. H. Evans. 2005. The Lower and Middle Ordovician cephalopod faunas of England and Wales. Monograph of the Palaeontographical Society 623:1-81
5. 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

• Dzik, Jerzy (1984) Phylogeny of the Nautiloidea, Palaeontologica Polonica, no. 43

v t e Notable fossil cephalopods (listed by first occurrence)
Cenozoic	The belemnite-cuttlefish-like Belosaepia	Evolution of cephalopods
Mesozoic	Advanced nautiloids Nautilaceae True ammonites Early coleoids Muensterelloidea Proteroctopus Styletoctopus Keuppia Palaeoctopus Paleocirroteuthis Vampyronassa Ceratitid ammonoids late Nautilida Advanced belemnoids Diplobelids: Diplobelus Belemnites: Belemnites Belemnopsis Belemnotheutis
Palaeozoic	Earliest unambiguous cephalopods: Plectronocerida: Plectronoceras, Monoplacophora-like form: Knightoconus? First appearance of long-lasting lineages Goniatite and ceratite ammonoids Probable coleoid ancestor Bactritida Early coleoids: Jeletzkya?, Gordoniconus, Syllipsimopodi Earliest belemnoids: Aulacocerids Phragmoteuthids Early forms the earliest cephalopod group Ellesmerocerida Orthocones: Endocerida, Orthocerida, Actinocerida Brevicones: Ascocerida, Oncocerida Earliest coiled cephalopods: Tarphycerida Spirulid?: Shimanskya
Misidentified	Probable misidentified genera Nectocarididae: (Nectocaris, Nectocotis) Kirengellida Volborthella Shelbyoceras Pohlsepia

• Orthocerida
• Prehistoric cephalopod families
• Ordovician first appearances
• Permian extinctions