Thailand names first mamenchisaurid dinosaur, a 20-meter Jurassic giant

Thailand has named Uragasaurus kalasinensis as its 15th officially identified dinosaur species, and the fossil places the country on the record as home to the first formally named mamenchisaurid dinosaur. A team led by Dr Apirat Nilphanaphan of Mahasarakham University described the species in Scientific Reports, based on a single, well-preserved anterior dorsal vertebra from the Phu Noi fossil site in Kalasin province.

The animal lived about 150 million years ago in the Late Jurassic and was a plant-eating sauropod with an unusually long neck. It reached up to 20 meters, or 66 feet, roughly the length of a cricket pitch. The specimen, catalogued as PRC 460, is housed at the Palaeontological Research and Education Centre at Mahasarakham University, where the bone was studied as part of a long-running fossil collection from the area.

Uragasaurus kalasinensis belongs to Mamenchisauridae, the long-necked dinosaur family that was especially abundant in East Asia during the Middle to Late Jurassic. Mamenchisaurids were known to be widespread in that region, but their diversity and spread outside China had remained poorly documented. The Phu Noi site itself first came to attention in 2008, after a local man found fragments that resembled serpent scales. Since then, the site in northeastern Thailand has yielded material from the Phu Kradung Formation, a Late Jurassic deposit in Thailand. Kalasin province has yielded Jurassic vertebrates before.