Dictionary of Ichthyology |
cycloid scale = a smooth-edged round or oval scale composed of acellular dermal bone lacking small spines on the posterior exposed edge. Typical of many Teleostei. Some cycloid scales may have a serrated margin and are then termed spinoid scales. |
Plaice scale showing four zones of annual growth from Lydekker et al. "Reptiles, Amphibia, Fishes and Lower Chordata", 1912. Photograph by Brian W. Coad. |