Shidaisaurus is an extinct genus of dinosaur that lived during the early Middle Jurassic period, about 174 million years ago. Its fossil remains were discovered in the Chuanjie Formation in Yunnan, China.
Shidaisaurus was first described in 2009 by a team of researchers led by Wu. The name “Shidaisaurus” refers to the Jin-Shidai Company, which was involved in its excavation.
This dinosaur belonged to a group known as theropods. These dinosaurs were mainly carnivorous and walked on two legs. Shidaisaurus was likely medium-sized, similar to its relatives.
The most notable features of Shidaisaurus include its skull, which shares many similarities with another dinosaur called Sinraptor. The preserved parts of its skull provide great insights into its appearance, including the structure of its teeth and braincase. Some unique characteristics of Shidaisaurus, known as autapomorphies, set it apart from other theropods.
Researchers estimate that Shidaisaurus could have been about 6 to 7.1 meters long, weighing between 700 to 950 kilograms. Its exact size can vary based on different studies.
The skeletal structure reveals that it likely had long neck vertebrae and some shared traits with related dinosaurs. However, due to missing parts, like the tail, the total length of its tail vertebrae is uncertain.
In short, Shidaisaurus was an interesting dinosaur that reflects the diversity of life during the Jurassic period. Its similarities to other theropods help scientists understand the evolution of these fascinating creatures.