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Family Physaliidae


Physalia utriculus

Portuguese Man-O'-War, Waimanalo Beach

Waimanalo Beach, Oahu


Common on beaches during periods of strong onshore winds.  Has a powerful sting.  Large ones have floats 3 to 4 inches long and the main tentacle may extend 10 feet or more.  Preyed upon by Violet Snails and Man-o-war Nudibranchs at sea and Ghost crabs & Mole crabs on beaches.  The rare Man-o'-War Fish takes refuge near the tentacles in the open ocean.  Hawaii & the Indo-Pacific.  The Atlantic Physalia physalis attains a float length of 12 inches and multiple tentacles attaining 30 feet.