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EveryFish

Cycloid and ctenoid scales

The two main scale types of bony fish: smooth-edged cycloid scales and comb-edged ctenoid scales.

Also: cycloid, ctenoid

Cycloid scales are thin and round with a smooth rear edge. Carps, herrings, salmon and trout have them, and they feel smooth when stroked. Ctenoid scales have tiny teeth, called ctenii, on the exposed rear edge, which make the skin feel rough when stroked from tail to head. Perches, basses, cichlids and many reef fish have them. Both types are made of a thin layer of bone and collagen, are flexible, and show growth rings. Some flatfish have cycloid scales on one side and ctenoid on the other.

See also

Scales Ganoid scales Otolith

Find fish that mention Cycloid and ctenoid scales

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