These rays vary in color from black to grayish blue along the back, and a white underside with grayish blotchs that have been used to identify individual rays. One of the distinct features of manta rays, and of the class Chondrichthyes, is that the entire skeleton is made of cartilage, which allows for a wide range of motion. The largest ever recorded was 9.1 meters. Manta rays show little dimorphism between the sexes with wingspan in males ranging from 5.2 - 6.1 meters and females ranging from 5.5 - 6.8 meters. Atlantic manta ray pups weigh 11 kg at birth and their growth is rapid, with pups virtually doubling the body width from birth through the first year of life. Manta rays also have a short, whip-like tail that, unlike many rays, has no sharp barb. The gills are located on the underside of the body. They have two cephalic lobes that extend from the front of the head and a broad, rectangular, terminal mouth containing small teeth exclusively in the lower jaw. Manta rays are easily reconized in the ocean by their large pectoral "wings." Manta birostris have no caudal fins and a small dorsal fin. ( Acker (MRBH), 2001 Bigelow and Schroeder, 1954) Atlantic manta rays stay closer to shore in the warmer waters where food sources are more abundant, but occasionally can be found further from shore. Manta birostris, unlike most other rays, are found near the surface of the ocean and to depths of 120 meters. ( Bigelow and Schroeder, 1954 FishBase, 1999 OceanLink, 1997) Manta rays are found in tropical and warm temperate coastal regions of the world's oceans, generally between 35 degrees north and south latitude, including the coasts of southern Africa, ranging from southern California to northern Peru, North Carolina to southern Brazil, and the Gulf of Mexico.
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