''Lametasaurus'' ( - meaning "Lameta lizard") named for the

Lameta Formation The Lameta Formation, also known as the Infratrappean Beds, is a sedimentary geological formation found in Madhya Pradesh, Gujarat, and Maharashtra, India, associated with the Deccan Traps. It is of Maastrichtian age (Late Cretaceous), and is nota ...

Jabalpur Jabalpur is a city situated on the banks of Narmada River in the state of Madhya Pradesh, India. According to the 2011 census, it is the third-largest urban agglomeration in Madhya Pradesh and the country's 38th-largest urban agglomeration. J ...

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

, is the generic name given to a possibly chimeric

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is t ...

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 Theropoda (; ), whose members are known as theropods, is a dinosaur clade that is characterized by hollow bones and three toes and claws on each limb. Theropods are generally classed as a group of saurischian dinosaurs. They were ancestrally c ...

dinosaurs. In 1923/1924 he named one of these as the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

''Lametasaurus indicus''. The generic name refers to the Lameta Formation, dating from the

Maastrichtian The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage) of the Late Cretaceous Epoch or Upper Cretaceous Series, the Cretaceous Period or System, and of the Mesozoic Era or Erathem. It spanned the interval from ...

, the specific name 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 Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms, similar to turtles. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. ...

; 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, ' ...

''. The

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

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 The tibia (; ), also known as the shinbone or shankbone, is the larger, stronger, and anterior (frontal) of the two bones in the leg below the knee in vertebrates (the other being the fibula, behind and to the outside of the tibia); it connects ...

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

titanosaur 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 th ...

armor Armour (British English) or armor (American English; see spelling differences) is a covering used to protect an object, individual, or vehicle from physical injury or damage, especially direct contact weapons or projectiles during combat, or fr ...

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 Alick Donald Walker (26 October 1925 – 4 December 1999) was a British palaeontologist, after whom the '' Alwalkeria'' genus of dinosaur is named. He was born in Skirpenbeck, near York and attended Pocklington School from 1936 to 1943. He began ...

chose the scutes as the

lectotype In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes the ...

, 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 ''Rajasaurus'' (meaning "princely lizard") is a genus of carnivorous abelisaurid theropod dinosaur from the Late Cretaceous of India, containing one species: ''Rajasaurus narmadensis''. The bones were excavated from the Lameta Formation in the ...

,'' 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 ''Ceratosaurus'' (from Ancient Greek, Greek κέρας/κέρατος, ' meaning "horn" and wikt:σαῦρος, σαῦρος ' meaning "lizard") was a carnivorous Theropoda, theropod dinosaur in the Late Jurassic Period (geology), period (Kim ...

'' 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 ''Indosaurus'' () is a genus of carnivorous theropod dinosaur that lived in what is now India, about 69 to 66 million years ago during the Maastrichtian division of the Late Cretaceous. The species I. matleyi weighed roughly 700 kg (1540&nbs ...

'' 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 In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular nam ...

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