Late Jurassic Sauropods in Chilean Patagonia

Abstract

Abstract. A description is provided of the first sauropod remains (i.e., isolated vertebrae and appendicular bones) from the Late Jurassic of Aysen, in Chilean Patagonia (Toqui Formation, late Tithonian). Although the bones found are fragmentary, they still allow the recognition of an unsuspected sauropod diversity for this period in South America. The materials suggest the presence of at least three different sauropod lineages: an indeterminate group of sauropods, possible Titanosauriformes, and Diplodocoidea. A phylogenetic analysis of this last clade supports the placement of the remains within Diplodocinae and also provides the first unequivocal record of this clade in Late Jurassic rocks of South America. These records provide important information about the poorly known evolutionary history of sauropods in South America before the Cretaceous.