Orthogoniosaurus

Orthogoniosaurus Temporal range: Late Cretaceous
Conservation status
Fossil
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
Superorder:	Dinosauria
Order:	Saurischia
Suborder:	Theropoda
Infraorder:	?Ceratosauria
Genus:	Orthogoniosaurus
Binomial name
Orthogoniosaurus matleyi Das-Gupta, 1931

Orthogoniosaurus (meaning "straight angled lizard", referring to the straight posterior edge of its type tooth) was a genus of theropod dinosaur from the late Maastrichtian-age Upper Cretaceous Lameta Formation of Jabalpur, India. It is based on one small, fragmentary tooth (preserved section 27 mm [1.1 in] long).^[1]

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 and Indosuchus.^[2] As a tooth taxon, however, such usage has been discouraged.^[3] Ralph Molnar 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.^[4] In the most recent review, it was considered to be a dubious ceratosaurian.^[5]

"Massospondylus" rawesi, another tooth taxon,^[6] but from probable Upper Triassic rocks, is sometimes given as a second species of this genus, but it may not be dinosaurian, and could be substantially older.^[7]

References

Dinosaurs portal

1. ^ 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.
2. ^ Romer, A.S. (1956). Osteology of the Reptiles. University of Chicago Press:Chicago 1-772. ISBN 0-89464985-X
3. ^ 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.
4. ^ 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. ISBN 0-520-06727-4
5. ^ 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. ISBN 0-520-24209-2
6. ^ Lydekker, R. (1890). Note on certain vertebrate remains from the Nagpur District. Records of the Geological Survey of India 23:20-24.
7. ^ Peter Galton quoted in: Glut, D.F. (1997). Dinosaurs: The Encyclopedia. McFarland & Company:Jefferson, North Carolina, p. 654. ISBN 0-89950-917-7.