Batoidea is a superorder of cartilaginous fishes, commonly recognized as rays. They, along with their close counterparts, the sharks, form the subclass Elasmobranchii. Rays stand out as the most extensive assemblage of cartilaginous fishes, encompassing a substantial assortment of over 600 species distributed among 26 families. The distinct characteristics of rays include their flattened anatomies, prominently developed pectoral fins that are fused to the head, and gill slits situated on their ventral surfaces.