Family: POTAMOTRYGONIDAE, Neotropical Stingray, Neotropical Stingrays, River Stingrays
NEOTROPICAL STINGRAYS, RIVER STINGRAYS
Small to large rays (disc width 25-180 cm); disc round to oval to weakly rhomboidal; tail variable; short, stout and muscular to very long, and whip-like; tail with lateral ridges, and with or without dorsal and ventral crests; tail stings vary from very robust to small and slender, to vestigial; head not elevated above disc; eyes usually small, but can be large and bulging; spiracles generally large; mouth with numerous tooth rows (upwards of 45), and 5 or more vertical papillae on floor; upper disc with numerous small denticles, sometimes large thorns or tubercles; many species (other than Styracura) are brightly colored.
A new world family of primarily freshwater species; 5 genera with ~30 species; one genus with a marine species on each side of the Central American isthmus.
PREPARED BY D ROSS ROBERTSON, AFTER LAST et al (2016)