Caseodontidae

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Caseodontidae
Temporal range: 315.2–247.2 Ma Early Carboniferous to Early Triassic
Life restoration of Caseodus, the type genus
The skull of Ornithoprion, an aberrant caseodont
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Order: Eugeneodontiformes
Clade: Caseodontoidea
Family: Caseodontidae
Zangerl, 1981
Type genus
Caseodus
Zangerl, 1981
Type species
Orodus basalis (=Caseodus basalis)
Cope, 1894
Genera

The Caseodontidae is an extinct family of eugeneodont holocephalans known from the late Paleozoic to earliest Mesozoic of Greenland, Canada and the United States.[1][2] Members of the group are characterized by a reduced or absent palatoquadrate, elongate upper and mandibular rostra, and bulbous, crushing dentition, including a small symphyseal whorl of teeth on the lower jaw and batteries of teeth fused directly to the neurocranium.[3][4] Several genera are known from partial or complete body fossils.[3][5]

Unlike the distantly related helicoprionids, members of this family crossed the Permian-Triassic boundary and persisted into the Olenekian stage of the Early Triassic,[5] after which they became extinct. It is hypothesized that in life caseodonts fed on hard-shelled prey such as brachiopods due to their crushing tooth batteries,[4] and it has been proposed that the elongated rostra on the upper and lower jaws of some genera was an adaptation for prying prey off of the seabed.[6] Well preserved specimens are known from the Carboniferous of Nebraska and Indiana,[3] deposits in East Greenland,[2] and from the Sulphur Mountain Formation of British Columbia, which is the last known appearance of the group.[5]

References

[edit | edit source]
  1. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  2. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  3. ^ a b c Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  4. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  5. ^ a b c Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  6. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).

Lua error in Module:Taxonbar at line 165: attempt to index field 'wikibase' (a nil value).