Biometric Characteristics of Sphyraena afra from Coastal Waters of Lagos State, Nigeria

Abstract

Meristic counts and morphometric measurements were carried out on Sphyraena afra from both off Lagos coast (LC) and Lagos lagoon complex (LLC) of Lagos state to evaluate the degree of variation among the populations as this will serve as a reference for sustainable fisheries management in the two environments.  Approximately 1249 individuals were sampled from the two water bodies. Nine meristic and 18 morphometric characters on each specimen were investigated. A principal component analysis (PCA) was performed to analyse meristic and morphometric variables. The population of the species among the two water bodies showed little variation in morphometric measurements and meristic counts which did not differ significantly (P≥0.05). The result revealed that only the first component accounted for the observed variations among the two populations studied and the PCA results showed that lateral line pores (LL) was the only character that shows significant contribution in species delineation. Differences observed in the lateral line pores may be attributed to environmentally induced changes rather than by genetic properties.

Keywords: Meristic, Morphometric, Sphyraena afra, Principal component analysis (PCA), Lateral line pores.