Marasuchus is a genus of dinosaur-like ornithodiran from the middle Triassic Period of Argentina. The species Marasuchus illoensis was originally described as a second species of Lagosuchus, L. lilloensis. However, in a restudy of Lagosuchus by Sereno and Arcucci (1994), the authors concluded that the original (type) specimen was too poorly preserved to allow any further specimens to be assigned to the genus. They also noted that the L. lilloensis specimen had limb proportions different from the type species. On this basis, they assigned L. lilloensis to a new genus, Marasuchus.