Sanxiasaurus (meaning "Sanxia lizard", after the Three Gorges, Chinese Sanxia, of the Yangtze River) is a genus of neornithischian dinosaur from the Middle Jurassic Xintiangou Formation in the Chongqing Municipality of China. The type and only species is S. modaoxiensis. The holotype is a partial postcranial skeleton consisting of 55 bones including two cervical vertebrae, 11 dorsal vertebrae, 4 sacral vertebrae, 18 caudal vertebrae, both humeri, radii, and ulnas, partial right ilium, partial right ischium, both femora and tibiae, left fibula, 3 metatarsi and 4 phalanges. In a phylogenetic ana
via Wikidata · CC0
Sanxiasaurus (meaning "Sanxia lizard", after the Three Gorges, Chinese Sanxia, of the Yangtze River) is a genus of neornithischian dinosaur from the Middle Jurassic Xintiangou Formation in the Chongqing Municipality of China. The type and only species is S. modaoxiensis. The holotype is a partial postcranial skeleton consisting of 55 bones including two cervical vertebrae, 11 dorsal vertebrae, 4 sacral vertebrae, 18 caudal vertebrae, both humeri, radii, and ulnas, partial right ilium, partial right ischium, both femora and tibiae, left fibula, 3 metatarsi and 4 phalanges. In a phylogenetic analysis, it was found to be a basal neornithischian, more derived than Lesothosaurus and less derived than Hexinlusaurus.
==History of naming== In 2016 a field team from the Chongqing Bureau of Geological and Mineral Resource Exploration and Development discovered a new fossil-bearing bed in the Xintiangou Formation of Laojun Village, Yunyang County. Excavations showed that the bed was rich in fossils with multiple outcrops around Laojun Village with many vertebrate remains found. Among these was 55 bones of a partial skeleton of an early ornithischian from a exploratory trench, away from the Fossil Wall of the Lower Shaximiao Formation. The Xintiangou Formation lies between the younger Lower Shaximiao and older Ziliujing Formation, with preliminary Uranium-lead dating giving it an Aalenian to Toarcian age of between 180 and 170 million years ago, during the Middle Jurassic. The ornithischian was the first of its kind from this formation and would be the oldest yet known from Asia. These remains, CLGPR V00003, were described in 2019 as the holotype of the new taxon by Chinese palaeontologist Ning Li and colleagues: Sanxiasaurus modaoxiensis. The genus name refers to Sanxia, the Three Gorges of the Yangtze River that covers the area where the taxon was found, while the species name refers to the Yangtze tributary Modaoxi. Multiple , both forelimbs and hindlimbs, and parts of the feet are known.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).