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The roach (''Rutilus rutilus''), also known as the common roach, is a fresh and brackish water fish of the Cyprinidae family, native to most of Europe and western Asia. The name "roach" is not unique, but fishes called roach can be any species of the genera ''Rutilus'' and ''Hesperoleucus'', depending on locality. The plural of the term is also roach.〔 〕 ==Description== The roach is basically a small fish, often reaching no more than about 35cm, maximum length is 45-50cm. The body has a bluish silvery colour and becomes white at the belly. The fins are red. The number of scales along the lateral line is 39-48. The dorsal and anal fins have 12-14 rays. Young specimens have a slender build; older specimens acquire a higher and broader body shape. The roach can often be recognized by the big red spot in the iris above and beside the pupil. Colours of the eye and fins can be very pale, however, in some environments. In Central and Northern Europe, the common roach can most easily be confused with the common rudd (''Scardinius erythropthalmus''), the dace (''Leuciscus leuciscus''), or the ide (''Leuciscus idus''). They can be distinguished, though, by the following characteristics: *The common rudd has a more yellow/greenish or golden colour. The backfin is placed more backwards and between the tip of the ventral scales and the first ray of the anal fin are only one or two scales. The roach has four or five scales there. The mouth of the rudd is more upturned and the head appears sharper. *The dace has a greenish body, colorless eyes and fins and a distinct 'nose'. *The ide has a higher number of scales along the lateral line (55-61), a rounder body, and a bigger mouth and head. 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「Common roach」の詳細全文を読む スポンサード リンク
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