Acanthurus gahhm, the black surgeonfish, monk surgeonfishorlined surgeonfish, is a species of marine ray-finned fish belonging to the familyAcanthuridae, the surgeonfishes, unicornfishes or tangs. This fish is found in the western Indian Ocean.
Acanthurus gahhm has a specific name, gahhm, which is an Arabic word for surgeonfish in the Red Sea.[6] It was thought to have been used by Peter Forsskål in 1755 but was described as an Arabic common name and not used as a valid specific name until Gmelin used it in 1789.[2]
This fish reaches up to 50 centimeters in length. It is oval in shape and laterally compressed. Like other surgeonfishes, it swims with its pectoral fins. The caudal fin has a crescent shape. The mouth is small and pointed. The body is black to dark brown, with a white ring around the base of the tail and a yellow stripe around the eyes. The pectoral fins are tipped with yellow.[7]
Acanthurus gahmm is found in the north-western Indian Ocean where it is endemic to the Red Sea and the Gulf of Aden, records farther east are likely to be misidentifications of A. nigricauda.[1]
This is a demersal fish. It lives on reefs and in lagoons and other sandy areas up to 40 meters deep.[3]
This species is omnivorous, feeding on algae, zooplankton and other small invertebrates, and detritus. It is active during the day and may swim in groups or remain solitary.[8]
^Gerald R. Allen; Roger Steene; Paul Humann; Ned DeLoach (2003). Reef Fish Identification: Tropical Pacific. New World Publications, Inc. ISBN1878348361.
^Vilcinskas, A. La vie sous-marine des tropiques. Vigot, 2002. ISBN2711415252
