''Orthogoniosaurus'' (meaning "straight angled

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia al ...

", referring to the straight posterior edge of its

type Type may refer to: Science and technology Computing * Typing, producing text via a keyboard, typewriter, etc. * Data type, collection of values used for computations. * File type * TYPE (DOS command), a command to display contents of a file. * Ty ...

tooth A tooth ( : teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, t ...

) was a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

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 ...

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 ...

from the late Maastrichtian-age

Upper Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', ...

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 not ...

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 ...

. It is based on one small, fragmentary tooth (preserved section 27 mm (1.1 in) long).Das-Gupta, H.C. (1931). On a new theropod dinosaur (''Orthogoniosaurus matleyi'', n. gen. et n. sp.) from the Lameta beds of Jubbulpore. ''Journal of the Asiatic Society of Bengal, New Series'' 16(20):367-369. Because it is the earliest published name for a Lameta theropod, it has sometimes been used as a synonym for other contemporaneous theropods, such as ''

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 The Maastrichtian () is, in the ICS geologic timescale, the latest age (uppermost stage ...

'' and ''

Indosuchus ''Indosuchus'' () is a genus of abelisaurid dinosaur from the Late Cretaceous Period (70 to 66 million years ago – the Maastrichtian), a theropod related to ''Abelisaurus''. Like most theropods, ''Indosuchus'' was a bipedal carnivore. It was ...

''. Romer, A.S. (1956). ''Osteology of the Reptiles''. University of Chicago Press:Chicago 1-772. As a tooth taxon, however, such usage has been discouraged.Walker, A.D. (1964). Triassic reptiles from the Elgin area: ''Ornithosuchus'' and the origin of carnosaurs. ''Philosophical Transactions of the Royal Society of London, Series B'' 248(744):53-134.

Ralph Molnar Ralph E. Molnar is a paleontologist who had been Curator of Mammals at the Queensland Museum and more recently associated with the Museum of Northern Arizona. He is also a research associate at the Texas natural Science Centre. He co-authored descr ...

in 1990 noted that the form of the tooth was most like teeth from the rear of theropod jaws, although the lack of serrations on the leading edge was unusual.Molnar, R.E. (1990). Problematic Theropoda: "Carnosaurs". In: Weishampel, D.B., Dodson, P., and Osmólska, H. (eds.). ''The Dinosauria''. Berkeley and Los Angeles: University of California Press:Berkeley and Los Angeles, p. 306-317. In the most recent review, it was considered to be a

dubious Doubt is a mental state in which the mind remains suspended between two or more contradictory propositions, unable to be certain of any of them. Doubt on an emotional level is indecision between belief and disbelief. It may involve uncertainty ...

ceratosauria Ceratosaurs are members of the clade Ceratosauria, a group of dinosaurs defined as all theropods sharing a more recent common ancestor with '' Ceratosaurus'' than with birds. The oldest known ceratosaur, '' Saltriovenator'', dates to the earlies ...

n.Tykoski, R.S., and Rowe, T. (2004). Ceratosauria. In: Weishampel, D.B., Dodson, P., and Osmolska, H. (eds.). ''The Dinosauria'' (second edition). University of California Press:Berkeley, 47-70. "''Massospondylus''" ''rawesi'', another tooth taxon,Lydekker, R. (1890). Note on certain vertebrate remains from the Nagpur District. ''Records of the Geological Survey of India'' 23:20-24. but from probable

Upper Triassic The Late Triassic is the third and final epoch of the Triassic Period in the geologic time scale, spanning the time between Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. T ...

rocks, is sometimes given as a second species of this genus, but it may not be dinosaurian, and could be substantially older.Peter Galton quoted in: Glut, D.F. (1997). ''Dinosaurs: The Encyclopedia''. McFarland & Company:Jefferson, North Carolina, p. 654. .

References

Ceratosaurs Late Cretaceous dinosaurs Dinosaurs of India and Madagascar Fossil taxa described in 1931 {{theropod-stub

See also

References