Species diversity and quantitative distribution of the surgeon fishes (Family: Acanthuridae) along Aqaba Gulf, Red Sea, Egypt

This study aims to estimate the diversity and distribution of surgeon fishes (Acanthuridae) on reef flat and slope along Aqaba Gulf, Red Sea. The inner reef flat of Aqaba Gulf is characterized by high non-living substrate, whereas at the middle reef the contributions of living materials are flourished with algae. On the other hand, the outer reef flat and slope are characterized by welldeveloped coral communities. On the Egyptian coast of Aqaba Gulf, the total number of the surgeon fish was 8 species (Acanthurus gahhm, A. nigrofuscus, A. sohal, Ctenochaetus striatus, Naso lituratus, N. unicornis, Zebrasoma desjardinii and Z. xanthurum). A. nigrofuscus and C. striatus were abundant at most sites. The southern sites have the highest number of species, while the northern ones were the lowest. The patterns of habitats play a role in the species distribution of the acanthurids; some preferred the reef flat (A. nigrofuscus, A. sohal and C. striatus), while others preferred the reef slope (A. gahhm, N. lituratus, N. unicornis, Z. desjardinii and Z. xanthurum). Most acanthurids have territories on reefs. A. sohal has large territories on outer reef flat. An analysis of the fish fauna confirmed that there are differences between northern and southern parts of Aqaba Gulf in terms of fish assemblages