Epachthosaurus (meaning "heavy lizard") was a genus of dinosaur from the Late Cretaceous. It was a titanosaurid sauropod. Its fossils have been found in Central and Northern Patagonia in South America.
The type species, E. sciuttoi, was described by Powell in 1990. A nearly complete skeleton was described in 2004.
Powell, J. (1990). "Epachthosaurus sciuttoi (gen. et sp. nov.) un dinosaurio sauropodo del Cretácico de Patagonia (provincia de Chubut, Argentina)." Actas del Congreso Argentino de Paleontologia y Bioestratigrafia 5: p 125-128
* Epachthosaurus in the Dinosaur Encyclopedia at DinoRuss' Lair