Dino of the Week: Shuangbaisaurus

Type Species: Shuangbaisaurus anlongbaoensis

Classification: Dinosauria - Saurischia - Theropoda

Time Period: Early Jurassic

Location: China

Diet: Carnivore

Shuangbaisaurus was a theropod dinosaur from Early Jurassic China who’s become famous for the pair of thin, midline crests on its skull that extended backwards over its eyes. Shuangbaisaurus is one of several Jurassic theropods known to certainly have head crests; such crests have been positively found upon such Early Jurassic theropods as Dilophosaurus (from North America), Cryolophosaurus (from Antarctica), Sinosaurus (from China), and at least one species of Early Jurassic Coelophysis (from North America).  Other theropods such as Liliensternus of the Late Triassic, Dracovenator from Early Jurassic, and Lophostropheus from the Late Triassic and Early Jurassic are assumed to have head crests because of skull similarities to the known crested theropods (such as mysterious bumps and pitting on parts of the skull). The purpose of the crests are unknown, but most believe they served as sexual displays to attract mates or intimidate rivals, or as instances of species recognition. Though some scientists believe Shaungbaisaurus is none other than its Chinese contemporary Sinosaurus, the skull crests on the two differ (Sinosaurus’ crest doesn’t extend over the eyes), so most paleontologists believe them to be different genera rather than two species of the same kind of dinosaur.

Shaungbaisaurus’ length is unknown, as its known only from skull fragments, but its head stretched just under two feet long and robustly designed. This has led researchers to argue that it was a medium-sized theropod who could take down large prey. Its environment would’ve been populated by early ornithischians, numerous crocodylomorphs, turtles and amphibians, and early mammals and their relatives. The largest creatures of its habitat were the sauropodomorphs, such as the early sauropod Chinshakiangosaurus and the prosauropods Lufengosaurus, Yimenosaurus, and Yunnanosaurus. It’s likely it hunted sauropodomorphs in its Early Jurassic environment.