Open Paleo

Asiatyrannus

Zheng et al., 2024 AY-shuh-ty-RAN-us

From Asia (the continent where fossils were found) + Greek tyrannos (τύραννος) meaning 'tyrant'; overall meaning 'Asian tyrant'.

72.2–66.0 million years ago Maastrichtian, Late Cretaceous
Late Cretaceous stages

Asiatyrannus is an extinct genus of tyrannosaurine theropod dinosaurs from the Late Cretaceous Nanxiong Formation of China. The genus contains a single species, A. xui, known from a single specimen consisting of a skull and partial postcranial skeleton. Asiatyrannus is notable for its deep-snouted skull and small body size, in contrast to the gracile snout and larger size of the contemporary Qianzhousaurus. It represents the southernmost record of an Asian tyrannosaurid.

Diagnosis

  1. Two small, deep fossae on the lateral surface of the premaxilla just lateral to the anteroventral border of the external naris
  2. Large and sub-rectangular shaped maxillary fenestra
  3. Posterior protuberances of the nasals connect to form two separated medium low ridges
  4. Low ridge-like jugal accessory horn with the ventral margin of the anterior ramus curving ventrally anterior to the horn
  5. Lateral surface of the descending process of the postorbital with anterodorsally trending fine lineations
  6. Lateral surangular shelf extending to the posterior end of the surangular

Species

Asiatyrannus xui Zheng et al., 2024

Type species

Named for prominent dinosaur researcher Xu Xing and Xu's contributions to paleontological research in China.

Holotype
ZMNH M30360 , Zhejiang Museum of Natural History
Material
Articulated skull and disarticulated postcranial elements including caudal vertebrae and leg bones
Horizon
Nanxiong Formation, Maastrichtian, Late Cretaceous , 72.2–66.0 million years ago
Locality
Shahe Town, Jiangxi, China

References

  1. Zheng, W.; Jin, X.; Xie, J.; Du, T. (2024). The first deep-snouted tyrannosaur from Upper Cretaceous Ganzhou City of southeastern China. Scientific Reports 14(1). Springer Science and Business Media LLC. doi:10.1038/s41598-024-66278-5 zheng2024a
  2. Jones, B. (2026). The Princeton Encyclopedia of Dinosaurs: Theropods. Princeton University Press.

    Source of the mass and hip height estimates.

    jones2026c