Morphological measurements, length weight relationship and relative condition factor (Kn) of Obtuse barracuda Sphyraena obtusata (Cuvier, 1829) from South-eastern Arabian Sea

Abstract

The study investigated morphometric and meristic measurements, length-weight relationship (LWR) and relative condition factor (Kn) of the Sphyraena obtusata from south-eastern Arabian Sea from August 2019 to March 2020. Three hundred and fifty two specimens having a length and weight range of 16.5 – 30.1 cm and 29.54 – 155.20 g, respectively were analyzed for morphological measurements (13 morphometric and 11 meristic), LWR and relative condition factor. The maximum correlation were existed between standard length (r > 0.985), fork length (r > 0.979) and pre-dorsal length 1 (r > 0.942) among the various morphometric variables. A disparity in relative growth was noticed among the morphometric traits. The Regression coefficient b value clearly indicates that growth of all the morphometric characters were isometric in connection with the total length, except for pelvic length (negative allometric), body depth (positive allometric) and caudal depth (positive allometric) (p < 0.01). The length-weight relationship of the individual sexes (male, female) and pooled data is indicated as W = 0.02275 L^2.6033, W = 0.01786 L^2.6815 and W = 0.01945 L^2.6541 having the value of coefficient of determination (r²) as 0.9566, 0.9696 and 0.9658, respectively. The ‘b’ values for both males and females divulge negative allometric growth (p < 0.05). There was no significant difference for the relative condition factor (Kn) among the months and size groups.