Question

What is cycloid and ctenoid?

Answer 1

Cycloid

1. Fish scales are classified as cycloid or ctenoid.
2. Cycloid scales are smooth-edged scales found mostly in lower-order teleost fishes such as carp and salmon.
3. Cycloid scales are thin, round, or oval in form, with growth rings visible.
4. They are overlapping which allows for greater flexibility in movement.
5. Cycloid scales appear to be the inner layer of ganoid or cosmid scales.

Ctenoid

1. Ctenoid Scales are firmly attached, with numerous little comb-like teeth or spines on their exposed free and portions that are not overlapped.
2. Ctenoid scales provide predator defense.
3. Ctenoid scales are identical to cycloid scales, with the exception that they include spines along their free edges.
4. These scales are found in modern higher teleosteans.
5. Bass and crappie both have ctenoid scales.