What is "zigongosaurus"

Zigongosaurus (meaning " Zigong lizard") is a genus of sauropod dinosaur from the Middle Jurassic- Late Jurassic-age Shaximiao Formation of Zigong, Sichuan, China. Because of incomplete knowledge of Jurassic Chinese sauropods, it has been hard to interpret, with some sources assigning it to Omeisaurus, some to Mamenchisaurus, and some to its own genus.