Rays, with their flattened bodies and large wing spans, are related to sharks. They also have a skeleton composed of cartilage, not bone, and belong to the same subclass Elasmobranchii group of Batoidea cartilaginous fishes containing more than 500 described species in thirteen families.
Rays live in temperate and subtropical habitats ranging from close to shore to the extreme depths of the ocean. Some live in solitary state, others congregate together.
Rays use their powerful, wing-like pectoral fins to propel them through the water. Covered with a slimy-to-the-touch mucus, they can move quickly, or glide, and some can even leap above the water, as seen in this photo of a “flying” ray. A ray must swim, like sharks, continuously.
While the different families of rays share internal physical characteristics, differing families vary in appearance and other attributes. They have different shapes, sizes, color, fins, teeth, habitat, diet, personality, and method of reproduction.
Rays have a flattened body shape and an elongated tail. The pectoral fins are large and connected to the body to form the ray's "disc." The shape of the disc differs from species to species and may be circular, oval, wedge-shaped or triangular. Some body shapes are adapted for living on the seabed; others are adapted for almost constant swimming.
The ray's distinctive tail also varies from species to species. It ranges from stubby Shorttailed electric ray tail to the incredibly long tail on the whip-like sting rays. These tail spines can poison other animals when stung. Some rays have a series of thorns on their body as a defense against predators. The color variation among rays is huge. Color even varies from male to female in some species.
Rays range in size from just a few inches to over 22 feet wide. The smallest ray is the Short-nose electric ray, about 4 inches (10 cm) across and about 1 pound (0.5 kg) in weight. The biggest ray is the manta ray which can reach 22 feet (6.7 m) wide and many tons in weight.
All rays are carnivorous, but their diet and mode of hunting varies. Some like the manta ray are filter feeders, sieving small prey like microscopic plankton, small fish, and small crustaceans as they swim almost continuously. They funnel the food into their mouth while they swim, using two large, flap-like cephalic lobes which extend forward from the eyes. Some rays are active hunters of mollusks and crustaceans on the ocean floor. They dislodge their prey, grab it with the rostral lobes, crush it with the teeth and eat it. Electric rays stun their prey with electricity.
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