Tehuelchesaurus (tay-WAYL-chay-SAWR-us) is a genus of dinosaur. It is named in honor of the Tehuelche people native to the Argentinian province of Chubut, where it was first found. It was a moderately large (?15 m long) cetiosaur-like sauropod found in the Late Jurassic (Tithonian) Cañadon Calcareo Formation at Fernandez Estancia, Chubut Province, Patagonia, Argentina; known from a 50% complete skeleton (Holotype: MPEF-PV 1125 (Museo Paleontologico Egidio Fergulio)), lacking a skull, but including dorsal, sacral and caudal vertebrae, parts of the forelimbs and hindlimbs, parts of the shoulder girdle and pelvis, some rib fragments, and skin impressions.