Bienosaurus in Yunnan

Bienosaurus (meaning “Bien’s lizard”) is a genus of thyreophoran dinosaur from the Lower Jurassic (probably Sinemurian) Lower Lufeng Formation in Yunnan Province in China.

Discovery and species


In 1938, Bian Meinian, known in the West as Mei Nien Bien, discovered a fragmentary dinosaur skull. In 2001, Dong Zhiming named and described the specimen as the type species Bienosaurus lufengensis. The generic name honours Bian. The specific name refers to the Lufeng formation.

Bienosaurus is based on holotype IVPP V15311 (in 2001 incorrectly given the inventory number IVPP V 9612). It consists of a partial right lower jaw with teeth and several cranial fragments.


Dong in 2001 placed Bienosaurus in the Scelidosauridae, considering these to be part of the Ankylosauria. Later publications suggested a general position basal in the Thyreophora. In 2019 a study confirmed this, concluding Bienosaurus was a nomen dubium, possibly identical to Tatisaurusfrom the same formation.