Edaphodon

Taxobox


name = "Edaphodon"
fossil_range = Devonian to Late Cretaceous
regnum = Animalia
phylum = Chordata
classis = Chondrichthyes
subclassis = Holocephali
ordo = Chimaeriformes
subordo = Chimaeroidei
familia = Callorhinchidae
genus = "Edaphodon"
genus_authority = Buckland, 1838
subdivision_ranks = Species
subdivision = See text for species.
binomial =
binomial_authority =

"Edaphodon" was a prehistoric chimaeriforme fish genus belonging to the family callorhinchidae. "Edaphodon" was a type of rabbitfish, a cartilaginous fish related to sharks and rays, and indeed some rabbitfishes are still alive today. "Edaphodon" has under fifteen known species, all of which are extinct. Chimaeriformes first appeared during the Devonian period around 415 to 360 million years ago, but this particular genus was most prominent during the Late Cretaceous. All "Edaphodon" species were situated in the Northern Hemisphere, apart from "E. kawai", which was recently discovered in the Chatham Islands near New Zealand. This shows that the range of "Edaphodon" reached further than was previously thought.

Description

Like most other chimaeriformes, "Edaphodon" is known mainly from poorly preserved specimens; this is due to "Edaphodon" being part of the chondrichthyes group, which are made of cartilaginous materials. Thus only a few spine and tooth fragments remain in most cases. "E. kawai" has been compared to another prehistoric cartilaginous fish, "Ischyodus", which closesly resembles the rabbitfish "Chimaera monstrosa". Whether the "E. kawai" remains are actually "Ischyodus" remains is yet to be seen.

"Edaphodon" is very similar to other rabbitfishes in appearance - it had dark scales, and fed using "grinding plates" of teeth that didn't regrow, unlike sharks. It is assumed that it laid eggs in a leathery pouch like other rabbitfish, but no occurrences of this have been recorded. "Edaphodon" had a sloping head and a mouth on its underside, allowing it to graze along the bottom of the ocean like a land-dwelling herbivore.

pecies

"Edaphodon" has numerous species, all of which are extinct:

*"Edaphodon agassizi" - Buckland, 1835
*"Edaphodon antwerpiensis" - Leriche, 1926
*"Edaphodon bucklandi" - Agassiz, 1843
*"Edaphodon eyrensis" - Long, 1985
*"Edaphodon kawai" - Consoli, 2006
*"Edaphodon laqueatus" - Leidy, 1873
*"Edaphodon leptognathus" - ("has not been formally classified") Agassiz
*"Edaphodon minor"
*"Edaphodon mirabilis" - ("has not been formally classified")
*"Edaphodon mirificus" - Leidy, 1856
*"Edaphodon sedgwicki"
*"Edaphodon smocki" - Cope
*"Edaphodon stenobryus" - Cope
*"Edaphodon tripartitus" - Cope

References

*Consoli, C.P. (December, 2006). "EDAPHODON KAWAI, SP. NOV. (CHONDRICHTHYES: HOLOCEPHALI): A LATE CRETACEOUS CHIMAEROID FROM THE CHATHAM ISLANDS, SOUTHWEST PACIFIC." Journal of Vertebrate Paleontology 26(4):801–805.

External links

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