New materials of<i>Gasparinisaura cincosaltensis</i>(Ornithischia, Ornithopoda) from the Upper Cretaceous of Argentina

New material of Gasparinisaura cincosaltensis from the Río Colorado Formation (Upper Cretaceous) of northwestern Patagonia (Río Negro Province, Argentina) provides seven new characters that are interpreted as autapomorphies of the species: 1) four true sacrals; 2) first sacral rib not coalescent with second sacral rib; 3) long pubic peduncle of ilium; 4) absence of anterior intercondylar groove on femur; 5) both malleoli of the tibia approximately at the same level; 6) metatarsal II posteriorly compressed laterally; and 7) low ascendant process of the astragalus. A phylogenetic analysis of selected ornithopods indicates that Gasparinisaura cincosaltensis is the most plesiomorphic Euiguanodontia. A complete absence of hatchlings indicates that Cinco Saltos was not a nest site.