Tropical Two-wing Flyingfish

The Tropical Two-wing Flyingfish (Exocoetus volitans) is a widespread member of the flyingfish family Exocoetidae, notable for having only one enlarged pair of wing-like fins — the pectorals — unlike the "four-wing" Cheilopogon species that also have enlarged pelvic fins. It is found throughout the warm surface waters of the Atlantic, Indian, and Pacific Oceans, typically far from shore over deep oceanic water. As one of the most broadly distributed flyingfish species, it forms an important part of open-ocean food webs, serving as prey for tunas, billfish, dolphinfish, and seabirds. It is abundant and not considered threatened.

Identifying the Tropical Two-wing Flyingfish:

• Stout, cylindrical body, typically 20-30 cm long
• Dark blue to blue-black back fading sharply to a silvery-white belly
• A single large pair of clear to lightly tinted pectoral fins used as the sole gliding wings
• Small, unenlarged pelvic fins, unlike the four-wing Cheilopogon flyingfishes
• Short, blunt snout without an elongated beak

The lack of enlarged pelvic fins is the clearest way to separate this "two-wing" species from four-wing genera such as Cheilopogon and Hirundichthys, which glide using both fin pairs. Its relatively stocky body shape and largely unmarked, translucent pectoral fins further help distinguish it from species with mottled or banded wings.

Tropical Two-wing Flyingfish are truly oceanic, living at the surface of open, deep water far from continental shelves throughout the warm belt of the Atlantic, Indian, and Pacific Oceans, generally where sea surface temperatures exceed about 20°C. As epipelagic fish, they remain in the top few meters of the water column their entire lives, rarely approaching shore except where deep water lies close to coastlines. Their broad, circumtropical distribution makes them one of the most widely encountered flyingfish species on long-distance ocean voyages.

This species glides using only its large pectoral fins, launching from the surface at speed and soaring in relatively straight, shorter glides compared to four-wing flyingfishes that use pelvic fins for extra lift and steering. It feeds on planktonic crustaceans and other small organisms near the surface, typically in loose aggregations rather than tight schools. Tropical Two-wing Flyingfish are an important prey species for large pelagic predators such as tuna, dolphinfish, and marlin, as well as seabirds. Spawning occurs in open ocean surface waters, with buoyant or floating eggs that develop while drifting, unlike species that attach eggs to debris.