Datanglong is an extinct genus of theropod belonging to either Carcharodontosauria or Megaraptora. It existed during the Early Cretaceous (Barremian-Albian) in what is now southeastern China.[1]
In 2011, staff of the Geological Survey Research Institute at the village of Nazao, twenty kilometers southwest of the town of Datang, near Nanning in Guangxi, discovered the remains of a large theropod new to science. The dinosaur was named and described in 2014 as Datanglong guangxiensis, by Mo Jinyou, Zhou Fusheng, Li Guangning, Hunag Zhen and Cao Chenyun. The genus name combines a reference to the Datang basin with the Chinese word long, "dragon". The specific name refers to the province of Guangxi.[1]
Datanglong guangxiensis is known from one specimen, holotype GMG 00001, which encompasses vertebrae and hip bones. There is a series of vertebrae that begins with the last dorsal (back) vertebra (according to the descriptors the fourteenth), continues over the five sacral vertebrae, and ends with the second tail vertebra. The sacrum is attached to a left ilium with the upper parts of the left pubic bone and the left ischium, and one piece of the right ilium. The bones were found in a layer of the Xinlong Formation, which was deposited sometime during the Early Cretaceous.[1]
Datanglong is a large predatory theropod with a length of roughly 8 to 9 metres (26 to 30 ft). The specimen has a preserved length of about 0.7 metres (2.3 ft).[1]
The describing authors determined some distinguishing characteristics. The last dorsal vertebra has a pleurocoel, or pneumatic cavity, that is bounded by an enlarged posterior ridge between the diapophysis and the vertebral body, by the posterior ridge between the parapophysis and the vertebral body; and by the vertebral body itself. The rear dorsal vertebra has a well-developed horizontal ridge between the prezygapophysis and the parapophysis. The last dorsal vertebra has a parapophysis that protrudes more laterally than the diapophysis. The groove in the underside of the rear blade of the ilium, serving as an attachment to the musculus caudofemoralis brevis, is shallow and the "brevis shelf", the inner surface of the medial blade wall uncovered by it, is short and shaped like a ridge. The pubic peduncle of the ilium, to which the pubic bone is attached, at the rear side transversely expands to below.[1]
The last dorsal vertebra resembles those of the Ceratosauria in that the parapophysis, the lower rib joint process, extends beyond the diapophysis, the upper rib joint process. The vertebra is also clearly pneumatised but the succeeding sacral vertebrae of the sacrum are not. The first tail vertebra has a depression at the level of the probable ridge between the prezygapophysis and the parapophysis. This vertebra also has a straight chevron. The spinous processes of the tail vertebrae are broken but the remaining pieces are fairly long and expand upwards.