Ichthyodectiformes

Ichthyodectiformes Temporal range: Late Jurassic-Late Cretaceous
Xiphactinus audax Ichthyodectes ctenodon Cladocyclus gardneri Chirocentrites sp.
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	†Ichthyodectiformes
Suborder:	†Ichthyodectoidei
Family:	†Ichthyodectidae Crook, 1892
Subfamilies
Ichthyodectinae Saurodontinae and see text
Synonyms
Cladocyclidae Unamichthyidae

The family Ichthyodectidae (literally "fish-biters") is an extinct family of marine actinopterygian fish. Sometimes classified in the primitive bony fish order Pachycormiformes, they are now placed in their own order, Ichthyodectiformes, within the superorder Osteoglossomorpha. The type genus is Ichthyodectes, established by Edward Drinker Cope in 1870.

They were most diverse throughout the Cretaceous period, though Thrissops fossils are known from the Oxfordian-Kimmeridgian boundary in the Late Jurassic. Most ichthyodectids ranged between 1 and 5 meters (3–15 ft) in length. All known taxa were predators, feeding on smaller fish; in several cases, larger Ichthyodectidae preyed on smaller members of the family. Some species had remarkably large teeth, though others, such as Gillicus arcuatus, had small ones and sucked in their prey.

Systematics

The basal phylogeny is very badly resolved, leading to many ichthyodectids that are simply known to be rather primitive, but where nothing certain can be said about their precise relationships.

Basal or incertae sedis

• Amakusaichthys Yabumoto, Hirose and Brito 2020
• Cladocyclus Agassiz, 1841
• Cooyoo Bartholomai & Less, 1987
• Eubiodectes Hay, 1903
• Faugichthys Taverne & Chanet, 2000
• Heckelichthys Taverne, 2008
• Thrissops Agassiz, 1843
• Unamichthys Alvarado-Ortega, 2004

Subfamily Saurodontinae

• Gwawinapterus Arbour & Currie, 2011
• Prosaurodon Stewart, 1999
• Saurocephalus Harlan, 1824
• Saurodon Hay, 1830

Subfamily Ichthyodectinae

• Gillicus Cope, 1875
• Ichthyodectes Cope, 1870
• Vallecillichthys Blanco & Cavin, 2003
• Xiphactinus Leidy, 1870

References

• Haaramo, Mikko (2008): Mikko's Phylogeny Archive – Ichthyodectiformes. Version of 2008-MAR-11. Retrieved 2008-NOV-20.