Patterns description of hyperostosis observed in Atlantic moonfish Selene setapinnis and lookdown Selene vomer.

Hyperostosis manifests itself and develops differently in taxonomically related species. Radiographic images of individuals belonging to different size classes of Atlantic Moonfish Selene setapinnis and Lookdown Selene vomer were obtained from two different estuarine areas of Rio de Janeiro/Brazil. In S. setapinnis, hyperostosis occurred in 65.22% of the specimens analyzed in three different skeletal regions. All specimens of S. vomer had hyperostosis in four regions. Patterns of occurrence were detected in both species, and the affected regions did not coincide in the same bone region, except for the cleithrum. Hyperostosis in S. setapinnis were observed in high frequencies of seventh dorsal pterygiophore, whereas in specimens of S. vomer this condition was detected to a greater extent in the neural spines of the second abdominal vertebra and first to third caudal vertebrae. The data demonstrated a relationship between the sexual maturity and the occurrence and development of hyperostotic bones in ageing process of individuals. It is the first description of S. vomer with a hyperostosis phenomenon for the species on the Brazilian coast.