Biometry analysis of the black scorpionfish, Scorpaena porcus (Linnaeus, 1758) from the eastern Adriatic Sea

the black scorpionfish, Scorpaena porcus (Linnaeus, 1758), is one of the most common species of Scorpaenidae family in the Mediterranean and the adriatic Sea. apart from the adriatic, it is distributed in the whole Mediterranean, including the Black Sea, and along the eastern atlantic coast, from the British isles to the azores and the Canary islands (HUreaU & LitViNeNko, 1986). S. porcus is an inshore benthic species, inhabiting rocky and sea-grass bottoms and being most numerous in the adriatic at depths between 5 and 15 m (GrUBiŠić, 1982). However, its distribution depends on the time of the day, the depth, the type of the bottom landscape and the study area (PaSHkoV et al., 1999). the black scorpionfish represents an important fishing object for trammel nets in the eastern adriatic, and their proportion in catches increased in the 1962 – 1982 period (JarDaS & PaLLaoro, 1989). although the diet (JarDaS & PaLLaoro, 1991; arCULeo et al., 1993; Morte et al., 2001), reproductive biology and growth (BraDai & BoUaiN, 1988, 1991; JarDaS & PaLLaoro, 1992; koCa, 2002; SÀBat et al., 2004; BiLGiN & ÇeLik, 2009) of S. porcus have been studied in Mediterranean and adriatic waters, morphometric and meristic characteristics of this very abundant species have not been systematically analysed. Some data on individual meristic characters of the black scorpionfish are available (CaDeNat, 1943; eSCHMeYer, 1969; FiSCHer et al., 1987; JarDaS, 1996; La MeSa, 2005), but morphometry data are rare and incomplete (CaDeNat, 1943; eSCHMeYer, 1969). in description of species, knowledge of its biometry is necessary especially because specimens from different areas differ from one another in morphology. the aim of A sample of 450 specimens of the black scorpionfish, Scorpaena porcus (Linnaeus, 1758), from the middle and south Adriatic was biometrically analysed. The total length of all specimens ranged from 7.0 to 25.8 cm. Eighteen morphometric and eight meristic characteristics were determined. Sexual dimorphism was observed in seven morphometric measurements. There were no differences in meristic characters between sexes. Relative growth was studied by comparing changes in morphological characters with growth in standard and head length. The results obtained suggest the existence of one unique population of S. porcus in the Adriatic Sea.