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A mounted skeleton of Barapasaurus, and its osteology

Bandyopadhyay S., Gilette D.D., Ray S. & Sengupta D.P. In press. Osteolology of Barapasaurus tagorei (Dinosauria: Sauropoda) from the Early Jurassic of India. Palaeontology: 1-37.

The sauropod dinosaur, Barapasaurus tagorei, is known from the Early Jurassic Kota Formation (Sinemurian to Pliensbachian) of India. The taxon is represented by c. 300 bones that were found associated with large fossilized tree trunks and were collected from the interface of sandstone and mudstone units covering an area of c. 276 m2. The collection includes one partial skeleton; most of the remainder of the bones were disarticulated, disassociated and dispersed, but taphonomic analysis permits recognition of associated elements comprising several individuals. Skeletal anatomy of Barapasaurus includes several teeth, vertebrae from the caudal cervicals rearward to the terminal caudals, and most elements of the appendicular skeleton. Barapasaurus is characterized by spoon-shaped teeth with bulbous bases and grooves on the anterolabial and posterolingual sides of the crown, coarse tubercles on the carina, acamerate cranial and dorsal vertebrae, lateral laminae of the middle and caudal dorsal neural spines composed of spinodiapophyseal and spinopostzygapophyseal laminae, neural canal of the mid-dorsal vertebrae opens dorsally through a narrow slit into a large cavity and sacrum with four co-ossified vertebrae. Phylogenetic analysis reveals that Barapasaurus is basal in comparison with Vulcanodon and is removed from Eusauropoda.


The description is mostly based on a composite, mounted skeleton in exhibition in the Geology Museum of the Indian Statistical Institute (ISI), in which all the material described here is housed. The material studied here (including the holotype of *Barapasaurus*, a sacrum) is considered as conspecific, because there is no indication it includes different species [sic]. Also, the diagnosis includes at least one autapomorphy [that's better !] (a 'slit-like opening of the neural canal of the dorsal vertebrae') in addition to an unique combination of characters. The phylogenetic analysis of Bandyopadhyay et al. is based on a modified version of the data matrix of Uprchurch, Barrett & Galton (2007), resulting in the coding of about 50 percent of the matrix for *Barapasaurus* and replaced several of the characters coded by Upchurch et al. by question marks - especially those with ratio because of the lack of associated remains. Few clades have been recovered in the strict consensis of the 47 MPT obtained: Ornithischia, Plateosauridae, Anchisauridae, and (Sauropoda + *Blikanasaurus*), which is fully resolved. Other relationships are undeterminate here. *Barapasaurus* is removed from Eusauropoda (sensu Upchurch et al., 2007), and *Barapasaurus* is the sister taxon of (*Vulcanodon* + Eusauropoda sensu Upchurch et al., 1997).

It would be interesting to see if the position of *Barapasaurus* change (i.e: if it goes back to Eusauropoda) with the inclusion of the recently decribed basal sauropod (e.g., *Antetonitrus*, *Tazoudasaurus*) and close sauropodomorphs (e.g., *Aardonyx*).