Malarguesaurus (meaning "Malargue lizard" after the Malargüe Department of Mendonza Province) is a genus of titanosauriform sauropod dinosaur from the Late Cretaceous of Mendoza Province, Argentina. Its fossils, consisting of tail vertebrae, chevrons, ribs, and limb bones, were found in the upper Turonian-lower Coniacian Portezuelo Formation of the Neuquén Group. The type species, described by González Riga et al. in 2008, is M. florenciae.

Description

Described as a robust sauropod, it was initially described as being closely related to Ligabuesaurus and Phuwiangosaurus, and Mannion et al. (2013) more precisely recovered it as a member of Somphospondyli. The cladistic analysis of Patagotitan recovered Malarguesaurus as a close relative of the Asian Ruyangosaurus. Like other sauropods, Malarguesaurus would have been a large quadrupedal herbivore. Malarguesaurus is the second sauropod dinosaur discovered in Mendoza Province; the first is Mendozasaurus neguyelap.