Butterfly Flyingfish, Cheilopogon papilio
The Butterfly Flyingfish, Cheilopogon papilio, whose Spanish common name is volador mariposa, is a species in the family Exocoetidae, the Flyingfishes, known collectively as voladores in Mexico. Globally, there are twenty four species in the genus Cheilopogon, nine of which are found in Mexican waters, four in the Atlantic and five in the Pacific.
The Butterfly Flyingfish has an elongated broadly cylindrical body. They are blue-green dorsally and silvery ventrally. The anal fin is transparent and the dorsal fin is dusky. The pectoral fins are black with a narrow clear margin and tip. Juveniles have black dorsal fins and two fused black barbels under their chin. They have short heads with short blunt snouts and small mouths equipped with small teeth which have one point. The anal fin originates under the third dorsal ray and they have nine or ten rays (a key to identification), the caudal fin is deeply forked with the lower lobe being significant larger than the upper, the pectoral fins are set high on the body are long reaching beyond the anal fin origin and the pelvic fins, originating far back on the body are closer to the caudal fin than the gill cover, and reach past the anal fin origin. The lateral line is low on the body. They are covered with large smooth scales.
The Butterfly Flyingfish is an oceanic pelagic species found on the surface to depths of 65 feet. They reach a maximum length of 22.2 cm (8.7 inches), with this upper length limit being established by the fish photographed below. They feed on planktonic organisms and small fishes. In turn they are preyed upon by birds, dolphins, dolphinfish, marlins, porpoises, squids, and tuna. They have large pectoral fins and are capable of leaping and gliding considerable distances above the ocean surface. Reproduction is oviparous with the release of large sticky filaments that attach to floating or benthic weeds. They are found in all Mexican waters of the Pacific with the exception that they are absent from the northern half of the Sea of Cortez and from along the entire West Coast of Baja.
The Butterfly Flyingfish is not an overly straightforward identification as it looks very much like several other flyingfishes. Some can be quickly eliminated by the dorsal fin ray counts as they have at least eleven. The others include the Blackwing Flyingfish, Hirundichthys rondeletii (anal fin origin under the dorsal fin orgin), the Panamic Flyingfish, Prognichthys tringa (pelvic fins nearer gill cover than caudal fin base), the Sailor Flyingfish, Prognichthys sealei (white dorsal fin), and the Smallhead Flyingfish, Cheilopogon pinnatibarbatus (pelvic fins nearer gill cover than caudal fin base). The Butterfly Flyingfish are seldom seen by humans and due to their rarity, they are of limited value and interest to most.