Uragasaurus

Uragasaurus is a sauropod dinosaur, and the first mamenchisaurid known from Thailand. Mamenchisaurids exhibit the basic sauropod body plan, processing their herbivorous diet in their large gut. Uniquely, mamenchisaurid necks, like that of Uragasaurus, are proportionately long, even by sauropod standards.

Life reconstruction of a herd of five individuals of Uragasaurus kalasinensis inhabiting a Late Jurassic forest in Thailand, accompanied by a pair of rhamphorhynchoid pterosaurs and a metriacanthosaurid theropod. Artwork by Pakorn Chotchaiyaporn (Jæsica ẞababi).

Quarry map showing the spatial distribution of the holotype of Uragasaurus kalasinensis and associated materials from the Phu Noi Locality (g). PRC 460 (Uragasaurus kalasinensis holotype) is indicated in red. Associated sauropod elements include KS 34-586, KS 34-587, KS 34-588, and KS 34-602a–b, highlighted in yellow, green, blue, purple, and pink, respectively. The inset shows a close-up of the excavation grid highlighting the relative positions of the holotype and nearby associated materials. Each grid square represents 0.75 × 0.75 m.

Locality map and section diagram of Phu Noi Locality. The map of Thailand (a); The location of Phu Noi Locality and the distribution of Phu Kradung Formation, the northeastern region with the outline of Kalasin Province (edit by Kantanat Trakulveerayut) (b); the diagrammatic section of Phu Noi (applied from Chowchuvech et al.31) (c).

The holotype anterior dorsal vertebra of Uragasaurus kalasinensis (PRC 460) in anterior (a) and posterior (b) views. Digital rendering of the specimen in anterior (c), posterior (d), right lateral (e), left lateral (f), dorsal (g), and ventral (h) views. Asterisk refers to an autapomorphic character. The blue highlight indicates the pneumatic fossa and pleurocoel.