Puertasaurus

Puertasaurus reuili is a genus of enormous sauropod dinosaur, a member of Titanosauria, known from the Late Cretaceous of Patagonia, Argentina. The genus contains a single described species, Puertasaurus reuili. The holotype consists of a partial skeleton including limb bones and some vertebrae; no skull has been found. The name Puertasaurus references the Puerta de la Esperanza area near the discovery site; the species epithet honors Guillermo Reuil, a local fossil collector.

Size and morphology: It is among the largest known dinosaurs, though only fragmentary remains exist, so size estimates are imprecise. Estimates for length range around the upper 20s to mid-30 meters; body mass estimates range widely, from tens to over seventy tons. The femur and limb bones show robust construction for supporting enormous weight. Notable features are limited due to incomplete material; its placement within Titanosauria is based on pelvic and limb anatomy.

Discovery and significance: The remains were found in southern Patagonia and described in the mid-2000s. Puertasaurus contributes to understanding of sauropod diversity in South America during the Late Cretaceous and indicates that titanosaurs achieved extreme gigantism in Gondwanan ecosystems. The genus shares a broad affinity with other large titanosaurs but remains distinct due to unique combinations of postcranial bones.