Sargassum fish to the seaweed, where it is fertilised by the male. On hatching, each larva is surrounded by an integumentary envelope and has a large, rounded head, fully formed fins, and eyes with double notches. As the larva develops into a juvenile, this envelope fuses with the skin. This fish is preyed on by larger fish and sea birds. To avoid underwater threats, it can leap above the surface onto mats of weed. It can survive for some time out of water. Sargassum fish The sargassum fish, anglerfish, or frog fish ("Histrio histrio") is a frogfish of the family Antennariidae, the
Sargassum and "S. fluitans") have become holopelagic—reproducing vegetatively and never attaching to the seafloor during their lifecycles. The Atlantic Ocean's Sargasso Sea was named after the algae, as it hosts a large amount of "Sargassum". "Sargassum" was named by the Portuguese sailors who found it in the Sargasso Sea after the wooly rock rose ("Halimium lasianthum") that grew in their water wells at home, and that was called "sargaço" in Portuguese (). The Florida Keys and its smaller islands are well known for their high levels of "Sargassum" covering their shores. Gulfweed was observed by Columbus. Although it was formerly thought