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The adult Longfin batfish is commonly confused with the Orbicular batfish. It can easily be distinguished though by the dark blotch below the pectoral fin. It can reach up to 65 cm in length. These fish occur inshore and near seaward reefs up to a depth of 70 meters. They are frequently found in and around shipwrecks. Usually they are swimming in small groups and sometimes form large schools. Like most batfishes, this species is unafraid of divers. The Longfin batfish feeds on algae, zooplankton and small invertebrates.