Interspecific Variation in Body and Otolith Morphometrics of Three Sphyraena Species (Perciformes: Sphyraenidae) from the Eastern Coast of Libya

Abstract

This study investigated the morphological characteristics of the body and otoliths of three Sphyraenidae species (Sphyraena flavicauda, S. sphyraena, and S. viridensis) collected from the Benghazi coast, eastern Libya, during winter 2023. Morphometric measurements were recorded from the left side of each specimen, including total length, standard length, head length, eye diameter, snout length, eye height, maximum body height and width, caudal peduncle dimensions, head width, and total weight. Eight morphometric ratios were calculated to evaluate proportional differences among species. The length–weight relationship indicated isometric growth, with b values ranging from 2.39 to 2.68 and condition factors from 0.375 ± 0.00 to 0.531 ± 0.013. Otolith length, height, area, and sulcus features were measured, and indices such as rectangularity, circularity, SAL/OL, OSL/SAL, CUL/SAL, OH/OL%, S index, and relative otolith size were calculated. Significant differences in body and otolith morphometrics were detected among the species, providing reliable markers for identification and supporting Sphyraenidae management in Libyan waters.