Arabian Surgeonfish (Acanthurus Sohal)

The sohal surgeonfish or sohal tang, Acanthurus sohal, is a Red Sea endemic which grows to 16 in (40 cm) in the wild.[1] Its striking blue and white horizontal stripes have made it what many consider the 'poster fish' for the Red Sea reef environment. It is a valued aquarium fish.
Like other tangs, the sohal tang is compressed laterally, making it extremely maneuverable and fast along the reef. It has a horizontal, blade-like spine along the base of its tail on both sides, which folds into the fish, pointing anteriorly towards the head. During defense and aggression, tangs flick the spine at other fish or intruders, causing physical harm. The surgeonfish are named for this scalpel-like spine.
Its primary diet consists mostly of vegetable matter, but occasionally includes the flesh of other animals. Sohal tangs have been known to nip at clam mantles and soft large-polyp and small-polyp stony corals.
Its range includes all reef environments in the Red Sea, to 90 ft or deeper. It is one of the most aggressive tangs, and combined with its large size for a tang, is a dominant fish along the Red Sea reef. (From Wikipedia)

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