Camptosaurus ‭(‬Bent lizard‭)‬

Short Info

Camptosaurus ‭(‬Bent lizard‭)‬

Phonetic : Camp-toe-sore-us.

Named By : Othniel Charles Marsh‭ ‬-‭ ‬1885

Diet : Herbivore

Size : Estimated 5-8 meters long

Type of Dinosaur : Euornithopod

Type Species : C.‭ ‬dispar (type)

Found in : United Kingdom, USA

When it Lived : Late Jurassic, 155-145 million years ago

Camptosaurus (/,kaempt@’so:r@sKAMP-t@-SAWR@s) is one of the genus comprising beaked, plant-eating ornithischian dinosaurs from the Late Jurassic period of western North America. The name is a reference to ‘flexible Lizard’ (Greek kamptos (kamptos) meaning “bent” in sauros (sauros) which means lizard).


Camptosaurus dispar skeleton
★Kumiko★, CC BY-SA 2.0, via Wikimedia Commons


Camptosaurus is a comparatively well-built form with sturdy hindlimbs, and large feet, despite with four toes. Because of the distinct status of Uteodon , it is now unclear which of the materials of the Morrison Formation is related to Camptosaurus. The materials that can be identified as belonging to Camptosaurus dispar, which are from Quarry 13 were discovered in extremely deep layers, most likely dating to the Callovian-Oxfordian period. The biggest fragments found in later strata show adult animals greater than 7.9 meters (26 feet) in length, and 2 meters (6.6 feet) in the hips. Quarry 13 Quarry 13 are smaller, however. They’ve been reported to have reached six meters (19.7 feet) in length, and 785-874 pounds in body weight. In 2010, Gregory S. Paul gave an even more modest estimation of five meters and an estimated total weight of just half of a ton.

Some earlier reconstructions, including the ones made of Marsh and Gilmore were based on The skull from Theiophytalia and have an incorrect and more rectangular shape. The skull was triangular and had an elongated snout and with beak. The teeth are more compactly packed inside the jaw than similar Morrison euornithopods. The curator of the museum John Foster describes them as having “thick median ridges on their lateral sides and denticles along their edges,” These features were similar to however, they were “more fully developed” than the ones found in Dryosaurus. Camptosaurus teeth typically show excessive wear, which suggests that people belonging to the genus ate an incredibly tough diet plants.

On the 4th of September, 1879 William Harlow Reed in Albany County, Wyoming found the remains of a tiny euornithopod. In the same year, Professor Othniel Charles Marshall described and named the site as Camptonotus, also known as “flexible back”, from Greek kampto, “to bend” and noton, “back”, in reference to the supposed the flexibility of the sacral vertebrae. The Holotype is YPM 1877, a part of a Skeleton. The genus was changed to Camptosaurus by Marsh in 1885 since the original name was used for crickets. The year 1879 was the time that Marsh identified C. dispar (type species belonging to the genus) for the materials he obtained from his collection at Quarry 13 close to Como Bluff, Wyoming in the Morrison Formation and C. amplus, based on the Holotype YPM 1879 that was discovered near Arthur Lakes at Quarry 1A. It was discovered to belong to Allosaurus. In the 1880s as well as the 1890s, Gilmore continued collect specimens of Quarry 13 and later in 1894 identified two species in addition: C. medius and C. nunus which was based on the size. Charles W. Gilmore named two species in addition, C. browni and C. depressus, in his 1909 redescription of Marsh specimens. The Morrison Formation, Camptosaurus fossils are located throughout the stratigraphic zone 2-6.

Then in 1980, Peter Galton and H.P. Powell in their re-description of C. prestwichi (see following) believed C. nunus, C. medius and C. browni to be distinct growth stages or a different genders of the larger C. dispar and thus the only C. dispar considered to be a valid species. They also believed that a skull, YPM 1887, which was published in 1886 was referred to as C. amplus, which was later confirmed by Marsh and later confirmed by Gilmore that it was a part of C. dispar too. Gilmore was using this skull to refer to what was the skull Camptosaurus however the specimen was recently proven by Brill and Carpenter not to be part of Camptosaurus. The year 2007 was the first time they placed it in its own species and genus Theiophytalia kerri.

Camptosaurus depressus was found in the Lakota Formation close to Hot Springs. Hot Springs, South Dakota. It was first described in 1909 by Charles Gilmore in 1909 based on the holotype, and the only one evidence USNM 4753, which is a fragmentary postcranium, based on its “narrowness or depressed nature of the ilia”. Carpenter Wilson and Carpenter Wilson (2008) have referred to that species Planicoxa and identified it as P. depressa due to the similarities in its ilium to the Holotype ilium from Planicoxa venenica. But, McDonald and colleagues (2010) as well as McDonald (2011) concluded that the postacetabular process horizontal in C. depressus may be to be a result of distortion. This is why McDonald classified it as a species in its own genus Osmakasaurus. A different specie, Camptosaurus Aphanoecetes was identified in the work of Carpenter as well as Wilson in 2008 in reference to specimens of Dinosaur National Monument. The species differs from C. differs with respect to the lower jaw. It also has its shorter neck vertebrae, and a straighter ischium that ends in a tiny “foot” among other features. A study conducted by Andrew McDonald and colleagues in 2010 indicated that C. Aphanoecetes, it is more closely related to advanced Iguanodonts (Styracosterna). It has been moved into the new Genus Uteodon.

While Marsh was writing about Camptosaurus species found in North America, numerous species from Europe were also included in the genus during the late in the 19th and beginning of 20th centuries. C. inkeyi C. hoggii C. leedsi C. prestwichi, and C. valdensis. C. inkeyi (Nopcsa 1900) is composed of fragmentary materials, which are a dentary, and an articular , derived from Upper Cretaceous rocks of the Hateg Basin in Romania. It’s almost certainly an rhabdodontid, and is therefore no longer believed to be valid (nomen dubium). C. valdensis is a dryosaurid that is a bit skewed, from the holotype as well as the only one specimen is known, NHMUK R167. It is a poor preserved left femur without the distal portion. It’s therefore difficult to evaluate it against other dryosaurids, such as the current Valdosaurus canaliculatus. C. leedsi is likely an authentic dryosaurid that was moved to the new Genus Callovosaurus. C. hoggii was originally known as Iguanodon hoggii in 1874 by Richard Owen in 1874 and was later transferred onto Camptosaurus through Norman Barrett and Norman Barrett after 2002. The species has since been moved to the Owenodon genus. Owenodon.

The last European specie Camptosaurus prestwichii was found in Chawley Brick Pits, Cumnor Hurst, Oxfordshire located in England. The fossil was discovered when the tramway was driven through the hill’s side. It was first described in the work of Hulke on 18th October 1880. It was referred to as Iguanodon prestwichii. Then, it was classified as a genus of its own Cumnoria in 1888 by Seeley in 1888. However, the fossil was later sunk in Camptosaurus in 1889 by Lydekker on 1889. But, Naish & Martill (2008), McDonald and colleagues (2010) and McDonald (2011) concluded that the original general distinction made by Seeley was correct. Cumnoria was identified as a styracosternan that is closer to advanced iguanodonts, than Camptosaurus dispar, as in the instance of Uteodon.

Source: Wikipedia