Evidence of denticles and attachment fibres in the superficial layer of scales in two fishes: Carassius auratus and Cyprinus carpio (Cyprinidae, Teleostei)

An attempt is made to clarify the mechanisms of the scale anchorage in two Cyprinidae, the goldfish and the carp. Scanning and transmission electron microscope investigations
revealed the presence of two different structures, denticles and collagen fibre bundles involved in the anchoring processes. These strucures are located on the upper part of the
scales. Denticles form minute processes on the circuli of the anterior areas of the scales. Collagen fibre bundles arise from the superficial layer connecting the scale to the overlying dermis. These fibre bundles show structural similarities with the Sharpey's fibres and are named Sharpey-fibre-like bundles. Such fibres of attachment, not previously reported, can be considered as usual anchoring structures in fish scales.