Salmon scale. Coloured scanning electron micrograph (SEM) of a salmon (Salmo salar) scale. Fish scales are are classified by shape. Salmon scales are

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Salmon scale. Coloured scanning electron micrograph (SEM) of a salmon (Salmo salar) scale. Fish scales are are classified by shape. Salmon scales are known as cycloid (curve edged). As the fish grows, the scale increase in size and growth rings called circuli become visible. During cooler months of the year the scale grows more slowly and the circuli are closer together leaving a band called an annulus. By counting the annuli it is possible to estimate the age of the fish. The exposed portion of the scale (upper half) is smoother and the rings less visible. Magnification: x19 when printed 10 centimetres wide.

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Size: 4800px × 4800px
Photo credit: © POWER AND SYRED/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, annular, annulus, biological, biology, circuli, concentric, cycloid, fauna, fish, growth, ichthyology, nature, overlap, overlapping, ringed, rings, salar, salmo, salmon, scale, sem, wildlife, zoological, zoology