Dravidosaurus is a nomen dubium, an unidentified prehistoric animal that may be related to Stegosaurus, but is just as likely not to be a dinosaur at all. It is mentioned in The Complete Guide To Prehistoric Life (Stegosaurus entry).
Facts
Dravidosaurus (meaning "Dravidanadu lizard", Dravidanadu being a region in the southern part of India where the remains were discovered) is a genus of prehistoric reptile which was once thought to be the last surviving stegosaur, the group of "plated" dinosaurs. With an estimated length of 3 metres (10 ft), it would have also been the smallest member of the group.
More recent studies, however, have shown that the bones actually belonged to a plesiosaurian marine reptile.
Dravidosaurus lived in the Late Cretaceous period (Coniacian stage) of what is now India. It is only known from a poorly preserved skeleton containing a partial skull, a tooth and some elements initially interpreted as plates. The badly weathered remains were discovered in marine deposits near Ariyalur in the state of Tamil Nadu in South India.
During the 1990s, further study indicated it was a plesiosaur and not a dinosaur.