The Sargassumfish, Histrio histrio, is a frogfish of the family Antennariidae, found close to the surface amongst floating sargassum weed in all subtropical oceans. Its length is up to 7.87 in (20 cm).

The Sargassumfish has numerous fleshy weed-like dermal appendages which allow it to blend in with the floating sargassum weed in which it is usually found. It is a deep-bodied shapeless species, with long and thickened pectoral and pelvic fins which serve as limbs allowing the fish to ‘walk’ amongst the seaweed fronds.

They lie in wait for passing crustaceans and small fish, lunging out suddenly to snap up their next meal.