Omeisaurus maoianus was named by Tang et al. (2001) [very low mid-cervical neural arches on very elongate centra; the long axis of the supratemporal fossa oriented transversely rather than anteroposteriorly; the anterior margin of supratemporal fossa formed entirely by the postorbital and parietal; the cervical pleurocoels subdivided by a bony septum that extends posteroventrally; tooth crown denticles best developed on the convex anterior crown margin and fewer in number on the concave posterior margin; dentary tooth counts up to 23; a larger external mandibular fenestra opened than that of other Omeisaurus and Mamenchisaurus , the minimum shaft diameters of metatarsals III and IV approach to that of metatarsal II; the ectopterygoid articulates laterally with the jugal; Muzzle-like region on snout is present.]. Its type specimen is ZNM N8510, a partial skeleton, and it is a 3D body fossil. Its type locality is Omeisaurus maoianus type-locality, which is in a Kimmeridgian/Tithonian terrestrial horizon in the Shaximiao Formation of China.