Yizhousaurus in Yunnan

Yizhousaurus is a genus of basal sauropodiform dinosaurs which existed in what is now Lower Lufeng Formation, Yunnan Province of southern China during the lower Jurassic period. Identified from a nearly complete and exquisitely preserved skeleton, it is the most complete basal sauropod currently known with intact skull. Although its name was revealed in a 2010 Geological Society of America abstract by Sankar Chatterjee, T. Wang, S.G. Pan, Z. Dong, X.C. Wu, and Paul Upchurch, it wasn’t validly named and described until 2018. The type species is Yizhousaurus sunae.

Discovery and Naming

  • Discovery: Fossils of Yizhousaurus were discovered in the Lower Jurassic-aged rock formations of Yunnan Province, China.
  • Name Origin: The genus name “Yizhousaurus” is derived from “Yizhou,” referring to the region where it was discovered, and “saurus,” meaning lizard in Greek.

Physical Characteristics

  • Anatomy: Yizhousaurus is known from partial skeletons, including elements of the skull, vertebrae, ribs, and limbs.
  • Size: It was a medium-sized prosauropod dinosaur, comparable in size to other early prosauropods, reaching lengths of about 4–6 meters (13–20 feet).

Classification

  • Prosauropod Dinosaur: Yizhousaurus belongs to the prosauropods, a group of herbivorous dinosaurs characterized by their bipedal stance and semi-grasping hands.
  • Position: It is considered an early member within the prosauropods and shares characteristics with other basal prosauropods from the Early Jurassic period.

Paleoecology

  • Habitat: During the Early Jurassic period, Yunnan was characterized by a warm, humid climate with lush vegetation. Yizhousaurus would have inhabited this terrestrial environment.
  • Contemporary Fauna: Yizhousaurus coexisted with other dinosaurs such as Lufengosaurus, Xingxiulong, early theropods, and various other herbivorous and carnivorous dinosaurs.

Significance

  • Early Prosauropod Diversity: Yizhousaurus contributes to our understanding of the early diversification of prosauropod dinosaurs. Its discovery in Yunnan expands the geographic range and temporal distribution of early prosauropods.
  • Paleontological Importance of Yunnan: The discovery of Yizhousaurus in Yunnan highlights the region’s significance in preserving Early Jurassic dinosaurs. It provides insights into the evolution and ecology of prosauropods during this period.

Yizhousaurus is an important fossil find that adds to our knowledge of prosauropod dinosaurs and the ancient ecosystems of Yunnan Province, China.