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The leafy seadragon or Glauert's seadragon,〔(【引用サイトリンク】title=Phycodurus eques )〕 ''Phycodurus eques'', is a marine fish in the family Syngnathidae, which includes seadragons, pipefish, and seahorses. It is the only member of the genus ''Phycodurus''. It is found along the southern and western coasts of Australia. The name is derived from the appearance, with long leaf-like protrusions coming from all over the body. These protrusions are not used for propulsion; they serve only as camouflage. The leafy seadragon propels itself by means of a pectoral fin on the ridge of its neck and a dorsal fin on its back closer to the tail end. These small fins are almost completely transparent and difficult to see as they undulate minutely to move the creature sedately through the water, completing the illusion of floating seaweed. Popularly known as "leafies", it is the marine emblem of the state of South Australia and a focus for local marine conservation.〔(【引用サイトリンク】title=The Leafy Sea Dragon ) Retrieved 17 August 2011.〕〔(【引用サイトリンク】title=Leafy and Weedy Sea Dragon )〕 ==Description== Much like the seahorse, the leafy seadragon's name is derived from its resemblance to another creature (in this case, the mythical dragon). While not large, they are slightly larger than most seahorses, growing to about 20–24 cm (8–10 in). They feed on plankton and small crustaceans. The lobes of skin that grow on the leafy seadragon provide camouflage, giving it the appearance of seaweed.〔Cott, Hugh (1940). ''Adaptive Coloration in Animals''. Oxford University Press. pp. 341–342.〕 It is able to maintain the illusion when swimming, appearing to move through the water like a piece of floating seaweed. It can also change colour to blend in, but this ability depends on the seadragon's diet, age, location, and stress level. The creature feeds by sucking up small crustaceans, such as amphipods and mysid shrimp, plankton, and larval fish through its long, pipe-like snout.〔 Leafy seadragons usually live a solitary lifestyle. When the time comes, males court the females, they then pair up to breed. From the moment they hatch, leafy seadragons are completely independent. By the age of two, they are typically full grown and ready to breed. The leafy seadragon is related to the pipefish and belongs to the family Syngnathidae, along with the seahorse. It differs from the seahorse in appearance, form of locomotion, and its inability to coil or grasp things with its tail. A related species is the weedy seadragon, which is multicoloured and grows weed-like fins, but is smaller than the leafy seadragon. Another unique feature are the small, circular gill openings covering tufted gills, very unlike the crescent-shaped gill openings and ridged gills of most fish species.〔(Lourie 1999).〕 Current research at the Scripps Institution of Oceanography is investigating the evolutionary relationships of the Syngnathidae and the DNA variation of the three seadragon species across their ranges.〔(【引用サイトリンク】title=Seadragon Phylogeography )〕 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「leafy seadragon」の詳細全文を読む スポンサード リンク
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