Temporal range: Late Jurassic-Late Cretaceous
156.0–66 Ma
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Ichthyodectiformes
Suborder: Ichthyodectoidei
Family: Ichthyodectidae
Crook, 1892

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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.


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[1]
  • 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

Subfamily Ichthyodectinae


  1. ^ "[PaleoIchthyology • 2020] Amakusaichthys goshouraensis • A New Ichthyodectiform Fish from the Upper Cretaceous (Santonian) Himenoura Group in Goshoura, Amakusa, Kumamoto, Japan".
  2. ^ Vullo, R., Buffetaut, E. and Everhart, M.J. (2012). "Reappraisal of Gwawinapterus beardi from the Late Cretaceous of Canada: a saurodontid fish, not a pterosaur." Journal of Vertebrate Paleontology, 32(5): 1198-1201. doi:10.1080/02724634.2012.681078


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