A basal iguanodontian (Ornithischia: Ornithopoda) from the Late Cretaceous of South America

ABSTRACT The ornithopod dinosaur Gasparinisaura cincosaltensis gen. et sp. nov. is described. This new taxon from the Upper Cretaceous of northwest Patagonia (Argentina) represents the first report of basal iguanodontian ornithopods from South America. Gasparinisaura shares with the Dryomorpha the out-turned jugal-postorbital articulation, prominent lateral primary ridge in maxillary teeth, well-developed brevis shelf and metatarsal I reduced or absent. It retains a well-developed quadratojugal, low maxillary crowns, and a laterally compressed ischial shaft. The new taxon Euiguanodontia is erected to include Gasparinisaura cincosaltensis and the Dryomorpha (=Dryosauridae + Ankylopollexia).