Janassa is an extinct genus of cartilaginous fish that lived in marine environments in what is now central United States of America and Europe during the Carboniferous and Permian periods. Janassa is known primarily from teeth, and a few poorly preserved, whole fossils from Germany. According to the fossils, Janassa had a body plan very similar to that of the modern skate. However, Janassa was a Petalodont, a kind of ancient cartilaginous fish related to chimaeras. Its teeth suggest it crushed and ate shellfish, such as brachiopods.