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Oarfish are large, greatly elongated, pelagic lampriform fish belonging to the small family ''Regalecidae''. Found in all temperate to tropical oceans yet rarely seen, the oarfish family contains four species in two genera. One of these, the giant oarfish (''Regalecus glesne''), is the longest bony fish alive, growing to up to in length. That is not enough to qualify as the longest fish, however, as some of the cartilaginous fish such as the basking shark and whale shark are even longer. The common name ''oarfish'' is thought to be in reference either to their highly compressed and elongated bodies, or to the now discredited belief that the fish "row" themselves through the water with their pelvic fins.〔 The family name Regalecidae is derived from the Latin ''regalis'', meaning "royal". The occasional beachings of oarfish after storms, and their habit of lingering at the surface when sick or dying, make oarfish a probable source of many sea serpent tales. Although the larger species are considered game fish and are fished commercially to a minor extent, oarfish are rarely caught alive; their flesh is not well regarded for eating due to its gelatinous consistency.〔( Davis, Josh L. Rare "Sea Monster" Washes Ashore In New Zealand. IFLScience )〕 == Anatomy and morphology == The dorsal fin originates from above the (relatively large) eyes and runs the entire length of the fish. Of the approximately 400 dorsal fin rays, the first 10 to 12 are elongated to varying degrees, forming a trailing crest embellished with reddish spots and flaps of skin at the ray tips. The pelvic fins are similarly elongated and adorned, reduced to one to five rays each. The pectoral fins are greatly reduced and situated low on the body. The anal fin is completely absent and the caudal fin may be reduced or absent, as well, with the body tapering to a fine point. All fins lack true spines. At least one account, from researchers in New Zealand, described the oarfish as giving off "electric shocks" when touched. Like other members of its order, the oarfish has a small yet highly protrusible oblique mouth with no visible teeth. The body is scaleless and the skin is covered with easily abraded, silvery guanine. In the streamer fish (''Agrostichthys parkeri''), the skin is clad with hard tubercles. All species lack gas bladders and the number of gill rakers is variable. Oarfish coloration is also variable; the flanks are commonly covered with irregular bluish to blackish streaks, black dots, and squiggles. These markings quickly fade following death. The giant oarfish is by far the largest member of the family at a published total length of —with unconfirmed reports of 〔( Bourton, Jody. Giant bizarre deep sea fish filmed in Gulf of Mexico. BBC Earth News )〕〔(Douglas Quenqua. Oarfish Offer Chance to Study an Elusive Animal Long Thought a Monster. ''New York Times''. 2 November 2013 )〕 specimens—and in weight. The streamer fish is known to reach 3 m (10 ft) in length,〔(【引用サイトリンク】title=''Agrostichthys parkeri'' (Benham, 1904) Streamer fish )〕 while the largest recorded specimen of ''Regalecus russelii'' measured 5.4 m (18 ft).〔 Oarfish are the longest known living species of bony fish. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Oarfish」の詳細全文を読む スポンサード リンク
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