"Pelagic stingrays are often seen feeding upside down. This fish uses its pectoral fins to put food in its mouth." - Coco
Pelagic Stingray is a fish that can be found on Paradise Island.
These inhabit the open ocean, and can be found in the deeper waters towards the corners of the map.
Some local NPCs may occasionally provide the following location hint after completing their quest:
"Pelagic Stingray can be caught both day and night, but only in the deepest waters."