''Lametasaurus'' ( - meaning "Lameta lizard") named for the Lameta Formation, Jabalpur, India, is the generic name given to a possibly chimeric dinosaur species.

History of discovery

Between October 1917 and 1919

Charles Alfred Matley Charles Alfred Matley (1866–1947) was a British paleontologist and geologist in India, the British West Indies and Wales. Matley was educated at Birmingham University, and earned a doctorate in geology (D.Sc.) from the University of London in J ...

excavated fossils near Jabalpur.Carrano, M.T., J.A. Wilson, P. M. Barrett, 2010, "The history of dinosaur collecting in central India since 1828", In: Moody, R.T.J., E. Buffetaut, D. Naish, and D. M. Martill (eds.), ''Dinosaurs and Other Extinct Saurians: A Historical Perspective''. Geological Society, London, Special Publications 343: 161–173 In 1921 he reported the find in the "Carnosaur Bed" of what he considered to be two megalosaurians, theropod dinosaurs. In 1923/1924 he named one of these as the type species ''Lametasaurus indicus''. The generic name refers to the Lameta Formation, dating from the Maastrichtian, the

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

refers to India. However, Matley no longer identified it as a theropod but as a member of the

Stegosauria Stegosauria is a group of herbivorous ornithischian dinosaurs that lived during the Jurassic and early Cretaceous periods. Stegosaurian fossils have been found mostly in the Northern Hemisphere, predominantly in what is now North America, Europe, ...

instead, which concept at the time also included the armoured dinosaurs today assigned to the Ankylosauria; at first Matley had seen it as a stegosaurian in the modern sense and even intended to name it as a species of ''

Omosaurus ''Omosaurus'' is a dubious genus of extinct crurotarsan reptile, possibly a phytosaur, from the Late Triassic (Carnian) of North Carolina. Only scant remains are known, which makes ''Omosaurus'' hard to classify. The type, and only species, ''O ...

''. The type specimen consisted of a number of dermal scutes, a

sacrum The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30. The sacrum situates at the upper, back part ...

of at least five

sacral vertebrae The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30. The sacrum situates at the upper, back part ...

, a

pelvis The pelvis (plural pelves or pelvises) is the lower part of the trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis, or pelvic skeleton). The ...

, a tibia and teeth. In 1933 Matley and

Friedrich von Huene Friedrich von Huene, born Friedrich Richard von Hoinigen, (March 22, 1875 – April 4, 1969) was a German paleontologist who renamed more dinosaurs in the early 20th century than anyone else in Europe. He also made key contributions about v ...

described some more remains collected by

Barnum Brown Barnum Brown (February 12, 1873 – February 5, 1963), commonly referred to as Mr. Bones, was an American paleontologist. Named after the circus showman P. T. Barnum, he discovered the first documented remains of ''Tyrannosaurus'' during a career ...

, thought to have been part of a tail club; later this was shown to be a large osteoderm. However, in 1935

Dhirendra Kishore Chakravarti Dhirendra Kishore Chakravarti (1902after 1985) was an Indian geologist and palaentologist, who worked at Banaras Hindu University in the Geological Museum (now part of the Institute of Science). In 1934, he was the first Indian to describe a s ...

contested the interpretation as an armoured dinosaur. He claimed that the specimen was a chimera including titanosaurid armor,

crocodile Crocodiles (family (biology), family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to inclu ...

teeth and theropod hindlimb material. In 1964 Alick Walker chose the scutes as the lectotype, thus removing the teeth and the bones from the type material. The name ''Lametasaurus'' now designated the scutes only and was generally considered to represent a member of the

Nodosauridae Nodosauridae is a family of ankylosaurian dinosaurs, from the Late Jurassic to the Late Cretaceous period in what is now North America, South America, Europe, and Asia. Description Nodosaurids, like their close relatives the ankylosaurids, wer ...

. The pelvis and hindlimb bones have in 2003 been suggested to belong to '' Rajasaurus,'' based on shared features in the . In 2008 Matthew Carrano e.a. discarded the possibility the scutes were ankylosaurian, stating they were probably

titanosaurian Titanosaurs (or titanosaurians; members of the group Titanosauria) were a diverse group of sauropod dinosaurs, including genera from all seven continents. The titanosaurs were the last surviving group of long-necked sauropods, with taxa still thr ...

, but noted that a comparison to the osteoderms of '' Ceratosaurus'' would help in determining its affinities. If in which case the species were to be found ceratosaurian, it would possibly be a senior synonym of '' Indosaurus'' and/or ''Rajasaurus.'' Most recently, it has been suggested that some of the osteoderms assigned to ''Lametasaurus'' show ankylosaurian synapomorphies, which renders ''Lametasaurus'' a chimera regardless of the affinities of the other material. The type material has been lost, lacking a known inventory number, making it difficult to test the several hypotheses. The taxon is today commonly seen as a ''

nomen dubium In binomial nomenclature, a ''nomen dubium'' (Latin for "doubtful name", plural ''nomina dubia'') is a scientific name that is of unknown or doubtful application. Zoology In case of a ''nomen dubium'' it may be impossible to determine whether a s ...

''.F.E. Novas, S. Chatterjee, D.K. Rudra and P.M. Datta, 2010, "''Rahiolisaurus gujaratensis'', n. gen. n. sp., a new abelisaurid theropod from the Late Cretaceous of India". In: S. Badyopadhyay (ed.), ''New Aspects of Mesozoic Biodiversity''. Lecture Notes in Earth Sciences 132, pp. 45-62

Notes

External links

Dinosauria Translation and Pronunciation Guide
*http://paleodb.org/cgi-bin/bridge.pl?a=basicTaxonInfo&taxon_no=57450 {{Taxonbar, from=Q285063 Invalid dinosaurs Late Cretaceous dinosaurs Dinosaurs of India and Madagascar Paleontological chimeras Taxa named by Charles Alfred Matley Fossil taxa described in 1923