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''Toxotes chatareus'', sometimes known by the common names seven-spot archerfish or largescale archerfish, is a species of perciform fish in the archerfish genus ''Toxotes''.〔Martin F. Gomon & Dianne J. Bray (2011) (Sevenspot Archerfish, Toxotes chatareus ). Fishes of Australia. Retrieved 29 Aug 2014〕 They are usually no larger than but may grow up to . Unlike most archerfish, ''T. chatareus'' are sooty rather than silvery in colour. They are omnivorous, feeding on insects, fish, and vegetative matter at the surface of the water. Breeding occurs in the wet season, and 20,000 to 150,000 eggs may be laid at one time. ''T. chatareus'' are distributed throughout southeast Asia and the Indo-Pacific and Australia. They may live in brackish or fresh water, inhabiting mangrove swamps and estuaries as well as further upstream in slow-moving rivers. While occasionally caught and eaten, ''T. chatareus'' are more commonly kept in the aquarium. They may be sold with other Toxotidae under the collective label "archerfish". Caring for ''T. chatareus'' in aquaria is somewhat difficult as they need live food given at the surface, rather than flake food. ==Description== ''Toxotes chatareus'' are of moderate size, usually between .〔 Rarely, they may reach up to in length. ''T. chatareus'' weigh up to . ''T. chatareus'' are believed to have a lifespan of three to five years.〔 ''T. chatareus'' have five or six dorsal spines, the fourth of which is the longest, and twelve or thirteen dorsal soft rays.〔 The dorsal spines are generally shorter in specimens collected from freshwater than those from brackish water.〔 ''T. chatareus'' also have three anal spines and fifteen to seventeen anal soft rays.〔 ''T. chatareus'' have 33 or 34 lateral line scales. The caudal (tail) fin in almost square.〔 The anal fin is undivided and the third anal spine is longest.〔 Overall, the body is sooty〔 but sometimes silvery or gold.〔 The dorsal side is "greenish brown".〔 The pectoral fins are clear or "dusky" in colour.〔 Pelvic fins may be darker and heavily pigmented.〔 ''T. chatareus'' are white and usually has six or seven dark blotches, alternating long and short, along the dorsal side.〔 A dark blotch is also found at the base of the caudal fin. The colour of these blotches may become darker or lighter due to time of day, environment, and stress.〔 The blotches of young fish are darker than those of older fish.〔 Startled or stressed fish are darker than unstressed fish; fish found in cloudy water may be completely white.〔 It is unknown whether sexual dimorphism occurs. 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「Toxotes chatareus」の詳細全文を読む スポンサード リンク
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