R is for Ray

Devil rays don't quite measure up to their manta ray cousins that weigh 4,000 pounds with a 25-foot wingspan. By contrast, devil rays are relatively small, measuring just 4 to 17 feet across. When it comes to agility, however, these 'mini mantas' could still take home the gold.

Devil rays, also called mobula rays, flap their wide fins to propel through the water. Breaking the surface with incredible speed, they soar up to 6 feet into the air. Then, with a spectacular flop, these underwater acrobats return to the sea.

Scientists have a few theories about why mobula, manta and eagle rays launch themselves out of the water. It may be a feeding strategy. Devil ray swarms have been observed with individuals jumping around the perimeter of the group, possibly driving prey in toward their fellow rays.

Flying out of the water could also be a mating ritual, means of escaping predators, method of communication, or attempt to remove parasites from their skin.

In addition to their great heights, devil rays also travel to extreme depths. The Chilean devil ray, or box ray, is one of the deepest-diving ocean animals, reaching depths of more than 6,000 feet.

The devil ray's skin is dark on top and light underneath. This countershading is a form of camouflage, helping the ray blend in with light from above and shadows below. The devil ray's skin is also covered in dermal denticles that give it a texture similar to sandpaper.

Cephalic fins on either side of the devil ray's head unfurl to help funnel water and food into the mouth on its underside. When tightly coiled, those fins resemble horns, earning devil ray its common name.

Devil rays live in temperate and tropical waters around the world, and many species are considered endangered, vulnerable or threatened. Fisheries target devil rays for their cartilage, which is used as filler in shark fin soup. The rays' gill rakers—filaments used to filter food from water—are also prized ingredients in traditional Chinese medicine.