Variability of the black scorpionfish, Scorpaena porcus (Scorpenidae) from two Black Sea localities

Abstract

The comparative investigation of morphological variability of the black scorpionfish, Scorpaena porcus from two distant Black Sea localities as villages Foros (Crimean Peninsula) and Malyy Utrish (Krasnodarskiy Kray) have been provided. Due to sexual dimorphism in the scorpionfish and the small number of males in the samples, only mature females were used in the analysis. A total of 54 individuals were examined (29 from the village of Foros and 25 from the village of Malyy Utrish). The two meristic and 26 morphomertic characters were in use. The region-related Differences between scorpionfish females from Foros and Malyy Utrish were not observed in the meristic characters, whereas were statistically significant in the morphometric characters, such as maximal body height; length of first dorsal fin; distance between pectoral and abdominal fins; the length of snout; eye diameter and length of lower jaw. The canonical discriminant analysis has shown that the scorpionfish females from Foros are correctly classified with an accuracy of 97%, while the females from Malyy Utrish with an accuracy of 100%.  It was suggested that obtained results are manifestations of modification variability. However, the significant differences between black scorpionfish females from two localities were not observed in the total length and body weight, which might be induced by differences in trophic conditions and the fish population size. This circumstance might testify the existence of complex of modification and interpopulation variability in S. porcus from the investigated Black Sea localities. In spite of pelagic eggs in S. porcus, which can be transferred with sea currents, the spatial isolation and limited migrations may lead to formation of local populations of the black scorpionfish. However, the analysis of genetic markers is needed for verification of the assumption. 

Keywords: Scorpaena porcus, morphological variability, interpopulation variability, isolation, the Black Sea