Postcranial Anatomy of a Late Triassic Sauropodomorph from Argentina

Apaldetti, C., Diego Pol, D.,  and A. Yates. 2012. The postcranial anatomy of Coloradisaurus brevis (Dinosauria: Sauropodomorpha) from the Late Triassic of Argentina and its phylogenetic implications. Palaeontology (Early View) DOI: 10.1111/j.1475-4983.2012.01198.x

Abstract - Basal sauropodomorphs from the Upper Triassic Los Colorados Formation
 of north-western Argentina have been known for several decades but
 most of them are only briefly described. New postrcanial remains of
Coloradisaurus brevis, the most gracile sauropodomorph from this unit,
are described here and evaluated within a phylogenetic context. These
materials belong to a single individual and include elements of the
vertebral column, pectoral girdle, incomplete forelimb, pelvis and
hindlimb. These elements share an autapomorphic feature with the type
specimen of Coloradisaurus brevis and provide novel and unique
features that diagnose this taxon, such as pubic apron with
semicircular cross-section and with a depression on its anterior
surface, distal surface of the tibia deflected and facing
posterodistally and well-developed pyramidal dorsal process of the
posteromedial corner of the astragalus. Several postcranial characters
of Coloradisaurus are exclusively shared with Lufengosaurus, from the
Lower Jurassic of China. The inclusion of this information in two
recent phylogenetic data sets depicts Coloradisaurus as closely
related to Lufengosaurus and well nested within Plateosauria. Both
data sets used indicate strong character support for the inclusion of
Coloradisaurus and Lufengosaurus within Massospondylidae.