Thornback Ray

Aquarium Inhabitant Bio

Platyrhinoidis triseriata


A particularly prickly ray. Can be identified by its small, heart-shaped body, long tail, and row of sharp thorns running down its back. One 15" Thornback present in this tank. Look closely, as it is often completely buried in the sand with only its eyes and breathing holes, called "spiracles," visible.

Habitat and distribution

Most commonly found in shallow coastal areas including bays and estuaries over sandy or muddy bottoms. Ranges from central California to Baja California.


Worms, Crustaceans (eg. crabs and shrimp), squids, and small fishes.

Fun Fact

As with other sharks and rays, the Thornback possesses special sensory organs called "ampullae of Lorenzini" that are capable of detecting the electric fields of potential prey items.