Distribution:
Tropical to polar seas, shallow to deep-water; Atlantic, Indian, and Pacific.
Remarks:
Skates and rays, a group of bottom-living cartilaginous fishes widely distributed in temperate and cold waters, and mainly in deep water in the tropics.
They are distinguished by their flattened body shape, with a quadrangular disc formed laterally by the enlarged pectoral fins, and a well developed thin tail. The tail fin is small, as are dorsal fins. Most species have weakly developed electric organs.
Fertilization is internal but the eggs are laid protected in a horny capsule. Eggs encased in horny capsule with four long tips.
Maximum total length about 2.5 m.
26 genera and 238 species. Subfamily Arphynchobatina (softnose skates) (11 genera, 83 species).
Subfamily Rajinae (hardnose skates) (15 genera, 155 species).
References:
Nelson 2006;
Wheeler 1975