The Main Characteristics of the Ray Fish Essay
Rays are primarily slow-moving, bottom-dwelling fishes of the oceans, the rays are close relatives of the sharks. Both, including skates, belong to the same class of fish, Chondrichthyes-vertebrates whose skeleton is composed of cartilage, not true bone. The terms skate and ray are often used interchangeably. Both fishes belong to the taxonomic order Batoidei, but the skates are classified in the separate suborder Rajoidei. Skates and rays occur in nearly all the oceans of the world, from shallow areas to depths of more than 8,900 feet . There are from 300 to 350 species of skates and rays. Most are flattened and more or less disk- or diamond- shaped, with large, winglike pectoral fins. The tail is generally slender and sometimes long and whiplike. In many species the tail has at least one sharp, venomous spine. Most of the skates and rays propel themselves with a graceful undulating movement of their pectoral fins, taking in water for respiration through large openings on the upper su...