Narrowhead Flyingfish, Cypselurus angusticeps
The Narrowhead Flyingfish, Cypselurus angusticeps, whose Spanish common name is volador isleño, is a species in the family Exocoetidae, the Flyingfishes, known collectively as voladores in Mexico. Globally, there are twelve species in the genus Cypselurus, two of which are found in Mexican waters, both in the Pacific.
The Narrowhead Flyingfish have elongated broadly cylindrical bodies. They are blue-green dorsally and silvery ventrally. Their anal fin is transparent, their caudal fin is dusky, their dorsal fin is pale gray, their pectoral fins are two-thirds red-gray and one-third clear, and their pelvic fins are pale with a dusky spot at the center of the base. They have a short narrow pointed head and a snout of similar length as the eyes. Their mouth is small with the lower jaw being a little shorter than the upper jaw and equipped with a limited number of three-pointed teeth. Their anal fin originates under the third dorsal ray and has eight or nine rays; their caudal fin is deeply forked with a longer lower lobe; their dorsal fin has twelve to fourteen rays; their pectoral fins are long and reach past the anal fin base; and their pelvic fins originate nearer the anal fin origin than the pectoral fin base. Juveniles have one broadly flattened barbel. Their lateral line is low on the body. They are covered with large smooth scales.
The Narrowhead Flyingfish are an oceanic pelagic species found on the surface to depths of 60 feet. They reach a maximum length of 24.0 cm (9.4 inches). They feed on planktonic organisms and small fish. In turn they are preyed upon by birds, dolphins, dorado, marlins, porpoises, squid, 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. In Mexican waters of the Pacific they have a limited range that includes the mouth of the Sea of Cortez from La Paz southward on the east coast of Baja and waters adjacent to Mazatlán along the coast of the mainland. They are a poorly studied species and very little is known about their behavioral patterns.
The Narrowhead Flyingfish is not overly straightforward to identify as it looks very much like several other flyingfish. Some can be quickly eliminated due to their dorsal fin ray count which is less than twelve. The exceptions are the Blackwing Flyingfish, Hirundichthys rondeletii (anal fin origin under dorsal fin origin) and the Smallhead Flyingfish, Cheilopogon pinnatibarbatus (pelvic fins nearer gill cover than caudal fin base).
The Narrowhead Flyingfish are seldom seen in North America due to their oceanic habitat, however, they are a commercial species in Southeast Asia where they are caught in coastal waters on moonless nights with lights and dip nets.