Biometrics of the Common Smooth-Hound Shark, Mustelus mustelus from Landing Sites of Lagos and Ondo Coasts (Nigeria)

This study investigates the biometrics of the common smooth-hound shark, Mustelus mustelus, from fish landing sites of the Lagos and Ondo Coasts. Morphometric measurements and meristic counts were used on 1,018 specimens to analyze morphometric differentiations. Significant sex-based differences were found across various morphometric traits, with phenotypically separable populations observed between locations. Bray-Curtis analysis categorized morphometrics into four groups based on similar characteristics. Principal component analysis identified three components, with PC1 dominated by chondrocranium and gill slit measurements, PC2 by gill slit and fin origin measurements, and PC3 by snout and fin origin measurements.