Cycloid

· Cycloid (for scales) = Gk word that describes the smooth rounded scales
· D
· Decapods = Gk word that describes invertebrate animals with 10 legs (shrimps, lobsters) ...

The Scales of a fish can be categorised into four basic types: placoid, cosmoid, ganoid and cycloid.
Placoid scales are found mainly on sharks, rays and their relatives and are similar in structure to that of teeth. They are rectangular in shape.

Batrachoidiformes: Body usually scaleless (small cycloid scales in some); head large with eyes more dorsal than lateral; mouth large and bordered by premaxilla and maxilla; pore (foramen) in axil of pectoral fin in some; ...

Asian arowana scales are large, cycloid, and, in some varieties, metallic coloured, with a distinctive mosaic pattern of raised ribs.

Definition: cyprinid [si'prainid, 'siprinid] - any teleost fish of the mainly freshwater family Cyprinidae, typically having toothless jaws and cycloid scales and including such food and game fishes as the carp, tench, roach, rudd, and dace.

See also: Water, Scale, Fish, Pelvic fin, Dorsal