Occurrence of hyperostotic pterygiophores in the silver scabbardfish, Lepidopus caudatus (Actinopterygii: Perciformes: Trichiuridae)

Background. Hyperostosis is a productive change characterized by an increase of the periosteal ossification combined with resorption of the bony tissue. It is common in several fish species. Its presence has been report- ed in the silver scabbardfish, Lepidopus caudatus (Euphrasen, 1788). The aim of the presently reported study is to improve the k nowledge on the presence of hyperostotic pterygiophores in L. caudatus. Materialsandmethods. In total, 50 specimens of Lepidopus caudatus, captured off the coast of Messina (Sicily, Italy) were examined by radiography. Deformed pterygiophores were decalcified and processed for histopatho- logical examination, and the sections obtained were stained with haematoxylin and eosin. Results. Forty (80%) of the 50 specimens examined showed skeletal deformities exclusively o n the pterygio- phores of the dorsal fin. In total, 433 deformities were observed. Histological examination showed slight expan- sion of the bone tissue, which was poor in cells and characterised by thin layers of compact bone tissue. Macroscopic, radiographic, and histological findings were consistent with diagnosis of hyperostosis. Conclusion. Hyperostosis of L. caudatus does not affect its consumption. However, it may be a complication for filleting t echniques as the presence of hyperostosis along the longitudinal axis of teleosts does not allow a com- plete and repeatable filleting technique. This could increase the possibility of bacterial contamination, loss of muscle tissue, and imperfections in cutting and trimming.

[1]  L. Jawad,et al.  On the record of pug-headedness in snapper, Pagrus auratus (Forster, 1801) (Perciformes, Sparidae) from New Zealand , 2007 .

[2]  T. Schlüter,et al.  Palaeopathological Fish Bones from Phosphorites of the Lake Manyara Area, Northern Tanzania – Fossil Evidence of a Physiological Response to Survival in an Extreme Biocenosis , 2002 .

[3]  J. Glowacki,et al.  Species-specific patterns of hyperostosis in marine teleost fishes , 1995 .

[4]  T. Schlüter,et al.  Hyperostotic fish bones (“Tilly bones”) from presumably Pliocene phosphorites of the Lake Manyara area, northern Tanzania , 1992 .

[5]  S. J. Olsen.  Swollen Bones in the Atlantic Cutlassfish, Trichiurus lepturus Linnaeus , 1971 .

[6]  J. Gaudant,et al.  Morphological and histological study of the hyperostoses of Lepidopus albyi (Sauvage, 1870), a fossil Trichiuridae from the Tortonian (Upper Miocene) of Piedmont (Italy) , 2010 .

[7]  K. Carpenter,et al.  Review of the crevalle jacks, Caranx hippos complex (Teleostei: Carangidae), with a description of a new species from West Africa , 2007 .

[8]  L. Capasso.  Antiquity of cancer , 2005, International journal of cancer.

[9]  L. Jawad.  First record of an anomalous mullet fish (Mugil cephalus )f rom New Zealand , 2004 .

[10]  E. Mesquita,et al.  Osteomas in cutlass fish, Trichiurus lepturus L., from Niteroi, Rio de Janeiro state, Brazil , 2002 .

[11]  P. Greenwood.  A redescription of the uniquely polychromatic African cichlid fish Tilapia guinasana Trewavas, 1936 , 1992 .

[12]  C. E. Dawson.  A Bibliography of Anomalies of Fishes , 1964 .

[13]  P. James.  INSTANCES OF EXCESSIVE THICKENING OF CERTAIN BONES IN THE RIBBON FISH, TRICHIURUS LEPTURUS LINNAEUS* , 1960 .