Xinjiangovenator

Xinjiangovenator (meaning "Xinjiang hunter") is a genus of coelurosaurian dinosaurs,[1] possibly part of the group Maniraptora, which lived during the Early Cretaceous period, sometime between the Valanginian and Albian stages.[2] The remains of Xinjiangovenator were found in the Lianmuqin Formation of Wuerho, Xinjiang, China, and were first described by Dong Zhiming in 1973. The genus is based on a single specimen, an articulated partial right lower leg, containing the tibia, three pieces of the fibula, the calcaneum and the astragalus. This specimen, IVPP V4024-2, is the holotype of the genus.[2]

The holotype was originally thought to be another specimen of Phaedrolosaurus.[3] However, Phaedrolosaurus is based only on a non-diagnostic tooth, so the hindlimb bones were given their own genus by Oliver Rauhut and Xu Xing in 2005. The type species is Xinjiangovenator parvus. The generic name is derived from the autonomous region of Xinjiang and Latin venator, "hunter". The specific name parvus means "small" in Latin.[2]

The lower leg (tibia plus ankle bones) has a length of 312 millimeters (12.3 inches). Gregory S. Paul estimated in 2010 that Xinjiangovenator individuals had a length of 3 meters and a mass of 70 kg.[4] Rauhut & Xu (2005) established two autapomorphies (unique derived traits) that could be used to characterize Xinjiangovenator. First, the lateral condyle (outer ankle joint) at the lower end of the tibia extends further backwards than the outer edge of the portion of the tibia near the knee. Secondly, the proximal part of the fibula (near the knee) has a longitudinal groove along its front edge.[2]