Describer

González Riga, Previtera & Pirrone 2008

Time

Cretaceous Late Turonian Coniacian

Classification

Saurischia Sauropodomorpha Sauropoda Titanosauria

Diet

Herbivore

Fossilsite

Portezuelo Formation of the Neuquén Group, Quebrada Norte quarry, Paso de las Bardas, Mendoza, Argentina

Info

Holotype

IANIGLA PV 110 (second species IANIGLA PV 111)

Malarguesaurus florenciae gen. et sp. nov. is a new and robust somphospondylian titanosauriform (Dinosauria, Sauropoda) from the Neuquén basin, Mendoza Province, Argentina. Collected by B. González Riga in 2005. The specimen comes from Upper Cretaceous strata assigned to the Portezuelo Formation (upper Turonian-lower Coniacian).

It includes proximal, middle and distal caudal vertebrae, chevrons, dorsal ribs, and appendicular bones. Malarguesaurus is characterized by the following association of characters: (1) proximal caudal neural spines vertically directed, with a concave caudal border, and a caudodorsal corner forming a right angle; (2) procoelous-opisthoplatyan proximal and middle caudal vertebrae associated with procoelous distal caudal centra; and (3) distal caudal neural spines having a concave and depressed dorsal border.

A preliminar cladistic analysis placed (Ligabuesaurus + (Malarguesaurus + Phuwiangosaurus)) as a sister taxon of Titanosauria. Unique among the titanosauriforms, Malarguesaurus has procoelous distal caudal centra associated with procoelous-opisthoplatyan proximal caudals. This discovery is a new evidence of the morphologic diversity of the South American sauropods.