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Clanwilliam yellowfish
The Clanwilliam yellowfish (''Labeobarbus capensis'') is a ray-finned fish species in the family Cyprinidae. It has long been placed in ''Barbus'', the "wastebin genus" for barbs, by default; however, the species is increasingly being restored to related yellowfish genus ''Labeobarbus'' which seems a much more appropriate placement. It is hexaploid like the other yellowfish, among which it is more closely related to the smallscale yellowfish (''L. polylepis'') than to the largescale yellowfish (''L. marequensis'').〔Impson & Swarz (2007), de Graaf ''et al.'' (2007)〕
As its relatives, this is a large species. They are silvery with blotchy vertical barring on the sides when young, and become light brown all over when adult. Males turn golden-yellow in the breeding season, and the common name refers to this.〔Impson & Swarz (2007)〕
==Distribution and ecology==
It is only found in the Western Cape Province of South Africa, where it is found in tributaries of the Olifants River, namely the Doring River, and the Biedou, Boskloof, Driehoeks, Groot, Jan Dissels, Kobee, Noordhoeks, Ratels, Rondegat, Thee and lower Twee Rivers in the Cederberg Mountains. It is not known whether it still occurs in the Olifants River itself in any numbers, and at least above Clanwilliam Dam and below Olifants Gorge it has apparently gone extinct.〔
''L. capensis'' is found in large and small rivers, but do not like slowly moving water. Young Clanwilliam yellowfish (below 4 cm/1.6 in long) are found in backwaters and shallow riffles. As they grow older they move out of the riffles into deeper water but even adults may still be found in relatively shallow parts of their habitat. The presence of deep pools and dense riparian stands of Palmiet (''Prionium serratum'', a Thurniaceae) that provide shadow will aid its survival if its home rivers run dry in hot summers. The young eat zooplankton and other small aquatic invertebrates. Adults are omnivores, feeding on larger invertebrates and algae. Their breeding season is prolonged and lasts from late spring to summer (about October to December), when the water is at least . During that time, adults repeatedly move in small groups into shallow riffles where the water is only a few decimetres deep, and deposit their non-sticky eggs there. The hatchlings initially move away from light and will hide between the substrate. In the absence of optimal breeding habitat (such as in dams), it will use any shallow water with generous rocks on the ground.〔
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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