What is the only fish known to fly by gliding above the ocean surface?

Flying fish are the fish best known for gliding above the ocean surface using enlarged fins.

They do not fly like birds or bats. Instead, a flying fish accelerates underwater, breaks through the surface, and spreads its greatly enlarged pectoral fins. Some species also have enlarged pelvic fins. Their lower tail lobe is longer than the upper lobe, allowing the fish to keep its lower lobe in the water for repeated propulsion during takeoff.

The resulting glide can carry a fish hundreds of metres, helping it escape predators such as tuna, mackerel, and swordfish. The fish may skim close to the surface and touch the water repeatedly, extending its airborne travel.

“Flying fish” refers to a family of marine fishes rather than one single species. They are found mainly in warm oceanic waters, especially in tropical and subtropical regions. Their gliding behavior is a classic example of escape evolution: the fish converts speed underwater into brief travel through the air.