Intra and interspecies discrimination of three teleost species collected from the Komo Estuary in Gabon in relation to living depth levels using otolith shape analysis

This study aimed to examine otolith shape and fluctuating asymmetry (FA) in pelagic Ethmalosa fimbriata, demersal Galeoides decadactylus, and benthic Cynoglossus monodi and assess their population status to inform on management procedures and verify whether or not otolith shape differs with living depth levels of these species in Lebe fishing site located along Komo Estuary, central-western Gabon. At intraspecies level, otolith shape analysis showed a bilateral asymmetry only in left and right otoliths between males and females of E. fimbriata and C. monodi. DFA separated between left and right and left-left and right-right otoliths shape of males and females within each species. At interspecies level, a significant bilateral asymmetry in left and right otolith shape was found among males and females of each species. DFA completely separated the left and right otoliths of both males and females of three species and confirmed the presence of three separate populations representing the three species, which should be managed separately. A significant FA on right and left otolith shapes was found among males and females at intra and interspecies levels. Accordingly, results indicated a close relationship between asymmetry of otolith shape and pelagic and benthic life characteristics of E. fimbriata and C. monodi.