Name:
Callovosaurus
(Callovian lizard).
Phonetic: Cal-lo-vo-sore-us.
Named By: Peter M. Galton - 1980.
Synonyms: Camptosaurus leedsi.
Classification: Chordata, Reptilia, Dinosauria,
Ornithischia, Ornithopoda, Dryosauroidea, Dryosauridae.
Species: C. leedsi (type).
Diet: Herbivore.
Size: Uncertain due to lack of remains, but
roughly estimated to have been about 2.5 meters long.
Known locations: England, Cambridgeshire -
Oxford Clay Formation.
Time period: Callovian of the Jurassic.
Fossil representation: Almost complete left femur
(thigh bone). A partial tibia (shin bone) is now also
attributed to the genus.
The
holotype specimen of Callovosaurus, an almost
complete femur, was
first described as a species of Camptosaurus
all the way back in
1889 by Richard Lydekker. By 1909 doubts were already being
cast as to whether or not this bone actually came from an iguanodontid
dinosaur. In 1980 Peter M. Galton took this femur and used it
to establish a new genus which we now know as Callovosaurus.
Callovosaurus
is seen as more likely to be a dryosaurid (relative of Dryosaurus)
dinosaur, rather than a large ornithopod like Camptosaurus.
However, because the genus is based upon a partial femur, many
have questioned its validity as it would be very difficult to assign
further fossil remains to this genus with only a partial leg bone to go
on. For this reason Callovosaurus is often cited
as a dubious
dinosaur genus, though a partial tibia has now also been assigned to
the genus.
As
a small dryosaurid ornithopod, Callovosaurus
would have been a small
ornithopod dinosaur that would have browsed upon low growing plants.
Callovosaurus would have shared its habitat with
other plant eating
dinosaurs including sauropods
and stegosaurs.
Further reading
- Osteology of the Jurassic reptile Camptosaurus,
with a revision
of the genus, and description of two new species. - Proceedings
of the United States National Museum 36: 197–332. - Charles
W. Gilmore - 1909.
- European Jurassic ornithopod dinosaurs of the families
Hypsilophodontidae and Camptosauridae. Neues Jahrbuch f�r Geologie
und Pal�ontologie, Abhandlungen 160(1):73-95. - Peter M.
Galton - 1980.
- Callovosaurus leedsi, the earliest dryosaurid
dinosaur
(Ornithischia: Euornithopoda) from the Middle Jurassic of
England, by Jos� Ignacio Ruiz-Ome�aca, Xabier Pereda Suberbiola
& Peter M. Galton. In Horns and Beaks: Ceratopsian and
Ornithopod Dinosaurs. Bloomington and Indianapolis: Indiana
University Press. - Kenneth Carpenter (ed) - 2007.