Antarctosaurus (meaning "southern lizard") is a genus of titanosaurian sauropod dinosaur from the Late Cretaceous Period of what is now South America. The type species, A. wichmannianus, was described by prolific German paleontologist Friedrich von Huene in 1929, who also described a second species in 1929. Three additional species of Antarctosaurus have been named since then. Later studies indicate that none of these pertain to Antarctosaurus.
Antarctosaurus was very large, even for a sauropod. Scientists still have much to learn about Antarctosaurus, as a complete skeleton remains elusive