Morphometric Analyses of the Angular Roughshark, Oxynotus centrina (Oxynotidae), with Biological Notes on Specimens from the Sea of Marmara

Morphometric measurements as percentages of total length of 6 specimens of Oxynotus centrina (Linnaeus, 1758), captured in the Sea of Marmara were reported. All of the analyzed proportions of landmark measurements as percentage of total length show allometry. Although, slight differences were seen between the morphometrics of Marmara specimens of O. centrina and those reported for the angular roughsharks captured in several geographical subregions of the Mediterranean Sea, these variations can be considered admissible based on allopatry. Regarding the mouth morphology in particular, the proportion of head length/mouth width to total length showed negative allometry, indicating O. centrina is a small-mouthed shark compared to increasing body size. A partly digested shark embryon and vitellus like slurry were found in the stomach content of one specimen captured in the Sea of Marmara, which provided supporting evidence for the predation on elasmobranch eggs by O. centrina in the wild.