Gobisaurus

Gobisaurus is an extinct genus of basal ankylosaurid ankylosaur from the Upper Cretaceous (Turonian) Ulansuhai Formation (Nei Mongol Zizhiqu) of China. The holotype (IVPP V12563) consists of a skull and as yet undescribed postcranial remains. This dinosaur was first named by Matthew K. Vickaryous, Anthony P. Russell, Philip J. Currie and Xi-Jin Zhao in 2001 and the type species is Gobisaurus domoculus.

This is a large ankylosaur, with a skull measuring 46 centimetres (18 in) in length and 45 centimetres (18 in) across. The name means "Gobi (Desert) lizard," referring to its discovery by the Sino-Soviet Expeditions (1959–1960) in the Gobi Desert. The genus is monotypic, containing only G. domoculus.

Gobisaurus and Shamosaurus
Gobisaurus domoculus shares many cranial similarities with Shamosaurus scutatus, including a rounded squamosal, large elliptical orbital fenestrae and external nares, a deltoid dorsal profile with a narrow rostrum, quadratojugal protuberances, and caudolaterally directed paroccipital processes. But the two taxa may be distinguished by differences in the length of the maxillary tooth row, an unfused basipterygoid-pterygoid process in Gobisaurus, the presence on an elongate vomerine premaxillary process in Gobisaurus, and the presence of cranial sculpting in Shamosaurus, but not in Gobisaurus. Vickaryous et al., 2004 found that a clade formed by Shamosaurus and Gobisaurus is "nested deep within the ankylosaurid lineage as the first successive outgroup to (the subfamily) Ankylosaurinae".