Dravidosaurus (meaning "Dravidanadu lizard", Dravidanadu being a region in the southern part of India where the remains were discovered) is an extinct genus of stegosaur dinosaur that lived in what is now India. It was thought to be the last surviving stegosaur, the group of "plated" dinosaurs. With an estimated length of 3 metres (10 ft), it would have also been the smallest member of the group. More recent studies, however, have shown that the bones actually belonged to a plesiosaurian marine reptile. However, later still, It's Stegosaurian Identity was reaffirmed.
Dravidosaurus lived in the Late Cretaceous period (Coniacian stage) of what is now India. It is only known from disassociated remains comprising a partial skull, a tooth, a sacrum, an ilium, an ischium, a dermal plate, and a spike. The badly weathered remains were discovered in marine deposits near Ariyalur in the state of Tamil Nadu in South India. They were in 1979 named by P.M. Yadagiri and Krishnan Ayyasami as the type species Dravidosaurus blanfordi, the specific name honouring William Thomas Blanford. The holotype partial skull is catalogued as GSI SR Pal 1, while other specimens are catalogued GSI SR Pal 2-7.[1]
In 1991, Sankar Chatterjee visited the site and claimed, without concrete morphological evidence, that Dravidosaurus is a plesiosaur, the species being a nomen dubium.[2] However, this claim was rejected Galton and Upchurch (2004), who noted that the skull, tooth and plate of Dravidosaurus are certainly not plesiosaurian.[3] Galton and Ayyasami (2017) reaffirmed the stegosaurian classification of Dravidosaurus by noting that stegosaurian remains from the Dravidosaurus type locality are under study by one of the original describers of Dravidosaurus.[4]
Description[]
Dravidosaurus is estimated to 3 meters (10 feet) long, but it is unknown what the animal actually was. Dravidosaurus was first identified as a stegosaur, consisting of a single plate, but has since been classified as a plesiosaur. Some, however, disagree with this saying Dravidosaurus is a sort of basal reptile. The remains aren't particularly dinosaurian, but have traits of a plesiosaur flipper. If Dravidosaurus is, in fact, a stegosaur, our understanding of stegosaur range will be tested. Dravidosaurus was dated to the Late Cretaceous, meaning it would be a Late Cretaceous stegosaur, a group that died out during the Late Jurassic.
JPInstitute.com Description[]
Until the discovery of Dravidosaurus, it was thought that all members of the stegosaur family died out before the end of the Jurassic. The discovery of this small plant-eater in India shows that stegosaur family members survived longer than scientists had thought, well into the Cretaceous. Not very much of this dinosaur has been found. However, from what was found, it seems to be much smaller than its more famous relative, Stegosaurus.
Recently, it has been suggested that the fossil remains of Dravidosaurus are not really dinosaurian, but rather that of a plesiosaur. As of this writing, however, the genus is still considered valid.
Links[]
http://web.archive.org/web/20040618235635fw_/http://www.jpinstitute.com/dinopedia/dinocards/dc_dravi.html https://web.archive.org/web/20080508051341/http://kids.yahoo.com/dinosaurs/313--Dravidosaurus
References[]
- ↑ Yadagiri, P., and Ayyasami, K., (1979). "A new stegosaurian dinosaur from Upper Cretaceous sediments of south India." Journal of the Geological Society of India, 20(11): 521-530.
- ↑ Chatterjee, S., and Rudra, D. K. (1996). "KT events in India: impact, rifting, volcanism and dinosaur extinction," in Novas & Molnar, eds., Proceedings of the Gondwanan Dinosaur Symposium, Brisbane, Memoirs of the Queensland Museum, 39(3): iv + 489–731 : 489-532
- ↑ Template:Cite book
- ↑ Peter M. Galton; Krishnan Ayyasami (2017). "Purported latest bone of a plated dinosaur (Ornithischia: Stegosauria), a "dermal plate" from the Maastrichtian (Upper Cretaceous) of southern India". Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen. 285 (1): 91–96. doi:10.1127/njgpa/2017/0671.