measuring long and weighing . In addition to the original fossils described by Lydekker in 1893, it is represented by fossils collected in the early twentieth century, and more recent material, including a well preserved and partially articulated specimen described in 2005 (with two associated osteoderms). Cervical vertebrae are known from multiple specimens of Neuquensaurus, although few are definitively associated with any other material. The centra are elongate, compressed vertically, and strongly , with an ovoid and rounded neural spine. Diagnostic of Saltasaurinae, the are shortened and robust and the extend far posteriorly to compensate. The lateral projections of the neural arch (transverse processes) are far more robust than in Isisaurus. As in the cervicals, the dorsal vertebrae bear strongly opisthocoelous centra with lateral pneumatic openings. In the dorsals, however, the pleurocoels are posteriorly pinched and internally subdivided, a regular feature of titanosaurs. The pleurocoels of Neuquensaurus are proportionally taller than in Trigonosaurus or Lirainosaurus. A ventral keel is lost throughout the dorsal series of probably 10 vertebrae, although the total count is uncertain. The vertebrae also lean less posteriorly towards the pelvis, initially inclined far beyond their individual centrum. However, they lack the of non-titanosaurs that limit vertebral motion. Two accessory are present in the dorsals of Neuquensaurus that are absent even in the close relatives Saltasaurus and Rocasaurus. Unique among all sauropods, the sacrum of Neuquensaurus is composed of seven vertebrae. The last vertebra is convex anteriorly and posteriorly, and diagnostically the middle vertebrae are strongly compressed in width. Like other derived titanosaurs, all caudal vertebrae of Neuquensaurus are strongly and vertically compressed. There is a prominent ventral depression like in Saltasaurus and Rocasaurus, but contrasting the other genera there is no ridge dividing this depression. Additionally, the neural spines of vertebrae become progressively more reclined, and a prespinal lamina is present in all vertebrae. Neuquensaurus has an almost complete skeleton. Among the preserved elements are a scapula. The scapula is co-ossified with the coracoid, a feature also found in Opisthocoelicaudia. In general aspect, the scapula resembles Saltasaurus, Opisthocoelicaudia, Lirainosaurus, and Alamosaurus. The coracoids of the scapulae are roughly quadrangular in shape, and are alike Saltasaurus and Lirainosaurus, but not Opisthocoelicaudia, Rapetosaurus, or Isisaurus, all of which have a rounded coracoid. Many characters distinguish Neuquensaurus from other titanosaurians. The features found by Otero in 2010 are: the possession of posterior caudal centra that are dorsoventrally flattened, and strongly