basking shark

basking shark, large, plankton-feeding shark, Cetorhinus maximus, inhabiting many oceans of the world, especially in temperate regions. Found singly or in schools of up to 100, it spends much of its time on or just below the surface, cruising slowly with its dorsal fin breaking water. It reaches a length of 40 ft (12 m) and weighs up to 8,500 lb (3,900 kg)—among fishes it is second in size only to the whale shark. It feeds by filtering out plankton as water passes into its mouth and out of the gills. Its gill openings are greatly enlarged to accommodate a large volume of water, and its throat is lined with numerous slender structures called gill rakers. These rakers, which are attached to the inside of the gill arches, form a fine mesh that serves as a strainer. The basking shark has a torpedo-shaped body, a nearly symmetrical tail fin, and long, conspicuous gill slits. Its color ranges from gray to black or brown. It is fished commercially, mostly by harpooning; its flesh is used for fish meal and its liver oil for certain tanning processes. It is classified in the phylum Chordata, subphylum Vertebrata, class Chondrichthyes, order Selachii, family Cetorhinidae.

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basking shark

Huge, sluggish shark (family Cetorhinidae) named for its habit of floating or slowly swimming at the surface. Possibly comprising more than one distinct species, it inhabits northern and temperate regions of the Atlantic, Pacific, and Indian oceans. It may grow as large as 46 ft (14 m); among fishes, only the whale shark grows larger. Despite its size, the basking shark feeds on plankton. It is gray-brown or blackish, with tiny teeth and very long gill slits. It is generally harmless and is hunted sporadically for fish meal and liver oil.

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basking shark

a very large plankton-eating shark, Cetorhinus maximus, often floating at the sea surface: family Cetorhinidae