Onychodus
Name: Onychodus
(claw tooth).
Phonetic: On-e-ko-dus.
Named By: Newberry - 1857.
Classification: Chordata, Sarcopterygii,
Onychodontida, Onychodontidae.
Species: O. sigmoides
(type), O. eriensis, O. jaekeli, O.
jandemarrai, O. yassensis.
Diet: Piscivore/Carnivore.
Size: Between 0.5 and 4 meters long
depending upon individual and species.
Known locations: Australia - Gogo Formation.
Canada - Dundee Formation. England. Germany. Norway.
Russian Federation. USA.
Time period: Eifelian to Famennian of the Devonian.
Fossil representation: Numerous individuals of
varying levels of completeness.
Onychodus
is a genus of large predatory fish that seems to have had a near global
distribution during the Devonian period. Onychodus
was a lobe-finned
fish with a pair of tooth whorls that grew large tusk-like teeth.
Onychodus was probably an ambush predator that
would quickly dart out
from cover to snatch unsuspecting fish as they swam by. One specimen
of Onychodus has been found with a placoderm fish
within its throat,
confirming that these types of fish perhaps among others formed part
of the diet of Onychodus.
Onychodus
also had what is known as a kinetic skull. This means that the skull
bones were not fused, but capable of moving around. The lower jaw
also lacked a hard bony joint with the skull, and was instead
connected by cartilage. These features would suggest that Onychodus
may have tried for very large prey, perhaps even larger than the
mouth would normally be. Once caught, the jaw would loosen up and
work its way over the prey in a similar manner to how we would see a
snake swallow an animal today.
Further reading
- On the Occurrence of the Devonian Ganoid Onychodus
in Spitzbergen.
- Geological Magazine. 6 (3): 499–500. - Aerthur Smith
Woodward - 1889.
- Onychodus jaekeli Gross (Crossopterygii,
Oberdevon) Bau des
Symphysenknochens und seiner Z�hne. - Senckenbergiana Lethaea.
46a: 123–131. - Walter R. Gross - 1965.
- Die Crossopterygier des Oberen Plattenkalkes (Devon) der
Bergisch-Gladbach-Paffrather Mulde (Rheinisches Schiefergebirge)
unter Ber�cksichtigung von amerikanischem und europ�ischem
Onychodus-Material. - Arkiv f�r Zoologi.
Series 2. 18:
305–389. - Hans L. Jessen - 1966.
- Arthrodire predation by Onychodus (Pisces, Crossoptergii)
from the Late Devonian Gogo Formation, Western Australia. -
Records of the Western Australian Museum. 15: 479–481. -
John Long - 1991.
- 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 Earth
Sciences 96:197. - Mahala Andrews, John Long, Per Ahlberg
& Richard Barwick - 2005.
- Morphological innovation through gene regulation: an example from
Devonian Onychodontiform fish. - The International Journal of
Developmental Biology. 50 (4): 371–375. - Ken Campbell
& Ricahrd Barwick - 2006.
- A large onychodontiform (Osteichthyes: Sarcopterygii) apex
predator from the Eifelian-aged Dundee Formation of Ontario, Canada.
- Canadian Journal of Earth Sciences 54:233-241. - A. Mann,
D. Rudkin, D. C. Evans & M. Laflamme - 2017.
----------------------------------------------------------------------------
Random favourites
 |
|
 |
 |