Temporal range: Early Cretaceous, 125–113 Ma
Holotype displayed in Japan in 2012
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Superfamily: Alvarezsauroidea
Genus: Bannykus
Xu et al., 2018
Type species
Bannykus wulatensis
Xu et al., 2018
  • Wulatesaurus (informal)

Bannykus is an alvarezsaur from the Early Cretaceous of the Bayin-Gobi Formation of Inner Mongolia, China. It includes one species, Bannykus wulatensis. It is large for an alvarezsaur, with an estimated weight of 24 kg based on femoral circumference.[1]


Scaled reconstruction

The holotype of Bannykus wulatensis is IVPP V25026, a partially-articulated incomplete skeleton. The holotype comes from the Bayin-Gobi Formation in Chaoge, Wulatehouqi, Inner Mongolia, China. It was discovered sometime prior to 2012, when its remains were displayed in Japan under the unofficial name "Wulatesaurus". It was given the binomial name Bannykus wulatensis in 2018; its generic name comes from the Mandarin word Ban (Chinese: ), meaning half, and the Greek word onyx, meaning claw. This refers to the transitional characteristics seen in this theropod. The specific name refers to Wulatehouqi (Wulate Rear Banner), the county that the holotype was found in.[1]


Bannykus, along with Xiyunykus, fills a 70-million year gap in alvarezsaur evolution by exhibiting morphologies intermediate between the typical theropod forelimb of Haplocheirus and the highly reduced forelimbs and minute teeth of Late Cretaceous alvarezsaurids.


  1. ^ a b Xu, Xing; Choiniere, Jonah; Tan, Qingwei; Benson, Roger B.J; Clark, James; Sullivan, Corwin; Zhao, Qi; Han, Fenglu; Ma, Qingyu; He, Yiming; Wang, Shuo; Xing, Hai; Tan, Lin (2018). "Two Early Cretaceous Fossils Document Transitional Stages in Alvarezsaurian Dinosaur Evolution". Current Biology. 28: 2853–2860.e3. doi:10.1016/j.cub.2018.07.057. PMID 30146153.