How many species of Stingrays are there?

Context: Stingrays are a group of sea rays, which are cartilaginous fish related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes and consist of eight families: Hexatrygonidae, Plesiobatidae, Urolophidae, Urotrygonidae, Dasyatidae, Potamotrygonidae, Gymnuridae and Myliobatidae. There are about 220 known stingray species organized into 29 genera.

Answer: There are about 220 known stingray species organized into 29 genera.