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Spotted galaxias (''Galaxias truttaceus'') is a largish, primarily-freshwater galaxias species found in southern Australia. Spotted galaxias are perhaps the most beautiful of the Australian galaxias species. They are a somewhat tubular, deep-bodied fish, with a dusky brownish-red colouration overlain with dark, haloed spots, dramatic black edges to dorsal, anal and pelvic fins, and a dark diagonal stripe through the eye. Spotted galaxias has a very wide distribution, being found in southern Victoria, all of Tasmania, offshore islands in between, as well as south-west Western Australia. On the mainland spotted galaxias is generally recognised as a freshwater fish species with a marine larval phase (larvae are swept out to sea and return to freshwater habitats as early stage juveniles), and thus only found in coastal rivers. Spotted galaxias are generally found in coastal rivers in Tasmania as well, however natural landlocked populations do occur in some freshwater lakes in Tasmania. Spotted galaxias were assumed not to be native to the Murray-Darling river system, however records of native fish fauna compiled by William Blandowski in the 1850s suggest the species did historically occur there. This may cause a re-evaluation of the spotted galaxias specimens occasionally recovered in the Murray-Darling river system, which until now were assumed to be accidental translocations via the Snowy Mountains Hydro-Electric Scheme. ==Habitat, diet, and reproduction== Spotted galaxias, in their juvenile and adult stages, inhabit coastal rivers at low to medium altitude. They prefer cool, flowing rivers in forested catchments with excellent riparian vegetation, good water quality and cover in the form of boulders, sunken logs and overhanging banks. Spotted galaxias are a predatory fish, feeding in the currents or "drift" similar to exotic trout species. Their diet consists mainly of aquatic and terrestrial invertebrates. Spawning occurs in winter in rivers. Larvae are swept out to sea and return and migrate back up rivers as early-stage juveniles which initially do not resemble adult fish. Returning juveniles are sometimes intercepted by humans as whitebait, and were severely overfished in previous decades. Landlocked lake populations spawn in spring. 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「Spotted galaxias」の詳細全文を読む スポンサード リンク
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