Onychodus

Onychodus
Temporal range: Eifelian–Famennian Devonian
Holotype skull of Onychodus jandemarrai (Showing single tusk whorl, while actually there should be a pair)
Scientific classification
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Onychodus

Species
Localities of known Onychodus fossils

Onychodus (/ɒˈnɪkədəs/, from Greek meaning "claw-tooth")[1] is a genus of prehistoric lobe-finned fish which lived during the Devonian Period (Eifelian - Famennian stages, around 374 to 397 million years ago). It is one of the best known of the group of onychodontiform fishes.[2][3] Scattered fossil teeth of Onychodus were first described from Ohio in 1857 by John Strong Newberry.[3][4][5] Other species were found in Australia, England, Norway and Germany showing that it had a widespread range.

Onychodus was about 2 to 4 meters in length and was a pelagic animal.[6] Like other onychodontiformes, it had a pair of tooth spirals (parasymphysial tooth whorls) bearing tusk-like teeth.

The most well-preserved specimen of Onychodus has been found in the Gogo Formation of Western Australia giving palaeontologists more information about the structure of the fish. Other species of Onychodus are known only from poor material based on isolated tusks, teeth and scales.[3]

  1. ^ Newberry, John Strong; Andrews, Ebenezer Baldwin; Orton, Edward (1870). Report of Progress in 1869. Reports of Progress. Ohio, USA: Ohio Geological Survey. p. 18.
  2. ^ Forey, Peter L. (1998). History of the Coelacanth Fishes. Springer. p. 259.
  3. ^ a b c Babcock, L. E. (2024). "Some vertebrate types (Chondrichthyes, Actinopterygii, Sarcopterygii, and Tetrapoda) from two Paleozoic Lagerstätten of Ohio, U.S.A." Journal of Vertebrate Paleontology. 44: 1–12. doi:10.1080/02724634.2024.2308621.
  4. ^ Hansen, Michael C. (1995). "Fossil fish found in American Aggregates Quarry (PDF)" (PDF). Ohio Geology. Summer 95: 5–6. Archived from the original (PDF) on 2009-01-01. Retrieved 2008-07-10.
  5. ^ Newberry, John Strong (1889). The Paleozoic Fishes of North America. Government Printing Office.
  6. ^ Andrews, Mahala; Long, John; Ahlberg, Per; Barwick, Richard; Campbell, Ken (2006). "The structure of the sarcopterygian Onychodus jandemarrai n. sp. from Gogo, Western Australia: with a functional interpretation of the skeleton". Transactions of the Royal Society of Edinburgh. 96 (3): 197–307. doi:10.1017/s0263593300001309. S2CID 84910707 – via ResearchGate.