Orthogoniosaurus


Orthogoniosaurus is a dubious genus of theropod dinosaur from the Late Cretaceous Lameta Formation of Jabalpur, India. It is based on one small, fragmentary tooth, with the preserved section measuring long.
Because it is the earliest published name for a Lameta theropod, it has sometimes been used as a synonym for other contemporaneous theropods, such as Indosaurus and Indosuchus. As a tooth taxon, however, such usage has been discouraged. Ralph Molnar in 1990 noted that the form of the tooth was much like that of teeth from the rear of theropod jaws, although the lack of serrations on the leading edge was unusual. In 2004 it was considered to be a dubious ceratosaur. Later studies have considered it to be an abelisaurid.
"Massospondylus" rawesi, another tooth taxon, is sometimes given as a second species. It was suggested that the tooth may not be dinosaurian, and could be substantially older. However, more recent research agrees on a Cretaceous age, and the tooth likely pertains to a theropod, possibly an abelisaurid.