Name: Rhabdodon
(Fluted tooth).
Phonetic: Rab-doe-don.
Named By: Matheron - 1869.
Synonyms: Oligosaurus adelus,
Ornithomerus gracilis
Classification: Chordata, Reptilia, Dinosauria,
Ornithischia, Ornithopoda, Iguanodontia, Rhabdodontidae.
Species: R. priscus
(type), R. septimanicus.
Diet: Herbivore.
Size: Four a long time thought to be about 4 meters
long, further discoveries indicate that adults actually ranged between
4 and 6 meters in length.
Known locations: Czech Republic, France, Romania
and Spain.
Time period: Late Campanian to Early Maastrichtian
of the Cretaceous.
Fossil representation: Multiple individuals.
Rhabdodon
is for lack of a better term a puzzle. Although usually described as
an iguanodont, Rhabdodon has also been considered
as a
hypsilophodont, and on top of this it has also been described as a
‘missing link’ between these two groups of dinosaurs. To further
the confusion however, Rhabdodon lived in the
late Cretaceous
period, long after these two groups diverged from another. If
Rhabdodon is indeed the form of this proposed
missing link, then it
is likely a very late surviving example of these dinosaurs, assuming
of course it is not a case of evolution repeating itself.
Rhabdodon
also has a complex classification history. Other similar dinosaurs
have been treated as being similar to it while some have actually been
suggested to be synonyms of it. Perhaps the best example here is
Mochlodon
which started out life as a species of Iguanodon
before being
raised as its own genus. Later study suggested it was a synonym to
Rhabdodon, though usually it is still regarded as
a distinct genus,
despite some sources labelling it as a synonym. In addition,
Rhabdodon is thought to be closely related to the
dinosaur Zalmoxes
which was established upon fossils originally assigned to Rhabdodon.
However Zalmoxes has also been treated as being
similar to Mochlodon
to the point that some palaeontologists have suggested that it could be
a synonym. If confirmed, and the other idea about Mochlodon
being a
synonym to Rhabdodon can be firmly established,
then this genus too
would become part of Rhabdodon once again.
The
relatively large number of Rhabdodon remains
indicates that it was one
of the principal plant eating dinosaurs of Europe during the late
Cretaceous. Back in the Cretaceous Europe was not the complete single
land mass that we know today, so the relatively small size of
Rhabdodon would have been a significant benefit for
the genus in
helping it to thrive in areas of limited surface area. Perhaps the
best example here is the increasingly famous Hateg Island, an island
community of dwarf dinosaurs that grew smaller than their mainland
counterparts. The large population numbers combined with small body
size of Rhabdodon meant that it was probably one of
the keystone prey
species of European ecosystems, though most of the known large
theropod dinosaurs of this time seem to have lived far away on other
continents such as Asia, North America and South America. However the
exact adult size of Rhabdodon adults seems to vary
considerably, with
the remains of adults seemingly coming from individuals between four
and six meters in length.
Threats
however still existed with smaller dromaeosaurids having both speed
and striking power to take down prey the size of Rhabdodon.
One
particular genus in mind could be Balaur,
a multi sickle clawed
dromaeosaurid seemingly built more for striking power than speed though
probably still easily fast enough to chase and catch a dinosaur like
Rhabdodon.
Further reading
- Note sur les reptiles fossiles des d�p�ts fulvio-lacustres cr�taces
du bassin � lignite de Fuveau [Note on the fossil reptiles from the
fluvio-lacustrine deposits of the Fuveau lignite basin]. - Bulletin de
la Soci�t� g�ologique de France, s�rie 2 26:781-795. - P. Matheron -
1869.
- Rhabdodon Matheron, 1869 (Reptilia,
Ornithischia): Proposed
conservation by suppression of Rhabdodon Fleischmann, 1831 (Reptilia,
Serpentes). Case 2536. - Bulletin of Zoological Nomenclature 43:
269-272. - W. Brinkmann - 1986.
- Rhabdodon Matheron, 1869 (Reptilia,
Ornithischia): Conserved. -
Bulletin of Zoological Nomenclature 45: 85-86. - ICZN Opinion 1483 -
1988.
- Phylogeny, Histology and Inferred Body Size Evolution in a New
Rhabdodontid Dinosaur from the Late Cretaceous of Hungary. - PLoS One.
2012; 7(9): e44318. - Attila Ősi, Edina Prondvai, Richard Butler
& David B. Weishampel - 2012.