Titanosaurus

Titanosaurus (meaning 'titanic lizard' – named after the mythological Titans, deities of Ancient Greece) is a dubious genus of sauropod dinosaurs, first described by Lydekker in 1877.[1] It is known from the Maastrichtian (Upper Cretaceous) Lameta Formation of India.

For the fictional character, see Titanosaurus (Godzilla).

Titanosaurus Temporal range: Late Cretaceous, 70 Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Titanosaurus indicus holotypic distal caudal vertebra
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Saurischia
Suborder:	†Sauropodomorpha
Clade:	†Sauropoda
Clade:	†Camarasauromorpha
Clade:	†Titanosauriformes
Clade:	†Somphospondyli
Clade:	†Titanosauria
Genus:	†Titanosaurus Lydekker, 1877
Type species
†Titanosaurus indicus Lydekker, 1877
Other species
†T. blanfordi Lydekker, 1879

Discovery and naming

Titanosaurus was the first Indian dinosaur to be discovered. The holotype vertebrae was discovered in 1828, but it was not officially named until 1877.[2]

Taxonomy

Titanosaurus is estimated to have grown up to 9–12 metres (30–40 ft) long and up to approximately 13 tons in weight. Wilson and Upchurch (2003) treated Titanosaurus as a nomen dubium ("dubious name") because they noted that the original Titanosaurus specimens cannot be distinguished from those of related animals.[3]

Species

T. blanfordi holotype distal caudal vertebra (GSI 2195)

As the type genus of Titanosauria, Titanosaurus at times became a wastebasket taxon for a number of titanosaurs, including those not just from India but also southern Europe, Laos, and South America. Only two among these, however, are currently considered species of Titanosaurus: T. indicus and T. blandfordi, both of which are considered nomina dubia.

Other species formerly referred to this genus include:

• "Titanosaurus" rahioliensis - Described based on teeth, this species is now considered an indeterminate neosauropod.[3]
• "Titanosaurus" colberti - This species was the most well-known species of Titanosaurus, but has been moved into its own genus, Isisaurus.[3][4]
• "Titanosaurus" australis - Known from relatively complete remains, but has been renamed Neuquensaurus.[3]
• "Titanosaurus" nanus - A small species found to be non diagnostic, and hence a nomen dubium.[3]
• "Titanosaurus" robustus - Now referred to Neuquensaurus.[3]
• "Titanosaurus" madagascariensis - nomen dubium; UCB 92305 apparently related to Vahiny, while UCM 92829 has been reassigned to Rapetosaurus.[3]
• "Titanosaurus" falloti - This large species, native to Laos, has disputed affinities. It has been considered synonymous with Tangvayosaurus and Huabeisaurus, but the remains are too fragmentary to be sure.[3][5][6]
• "Titanosaurus" valdensis - Referred to a new genus, Iuticosaurus, but still considered a nomen dubium.[3]
• "Titanosaurus" lydekkeri - Also referred to Iuticosaurus, but its relation to I. valdensis is uncertain.[3]
• "Titanosaurus" dacus - A dwarf titanosaur; now moved to the genus Magyarosaurus.[3]

References

1. Lydekker, R. (1877). "Notices of new and other Vertebrata from Indian Tertiary and Secondary rocks." Records of the Geological Survey of India, 10(1): 30-43.
2. "Pranay Lal: India has not marketed or preserved its discoveries on dinosaurs".
3. Wilson, J.A. and Upchurch, P. (2003). "A revision of Titanosaurus Lydekker (Dinosauria – Sauropoda), the first dinosaur genus with a “Gondwanan” distribution." Journal of Systematic Palaeontology, 1(3): 125-160.
4. Jain, Sohan L.; Bandyopadhyay, Saswati (1997). "New Titanosaurid (Dinosauria: Sauropoda) from the Late Cretaceous of Central India". Journal of Vertebrate Paleontology. 17 (1): 114–136. doi:10.1080/02724634.1997.10010958. Retrieved December 31, 2012.
5. Pang, Qiqing; Cheng, Zhengwu (2000). "A New Family of Sauropod Dinosaur from the Upper Cretaceous of Tianzhen, Shanxi Province, China". Acta Geologica Sinica. 74 (2): 117–125. doi:10.1111/j.1755-6724.2000.tb00438.x.
6. Allain, R.; Taquet, P.; Battail, B; Dejax, J.; Richir, P.; Véran, M.; Limon-Duparcmeur, F.; Vacant, R.; Mateus, O.; Sayarath, P.; Khenthavong, B.; Phouyavong, S. (1999). "Un nouveau genre de dinosaure sauropode de la formation des Grès supérieurs (Aptien-Albien) du Laos". Comptes Rendus de l'Académie des Sciences, Série IIA (in French). 329 (8): 609–616. Bibcode:1999CRASE.329..609A. doi:10.1016/S1251-8050(00)87218-3.