Ribbon Halfbeak, Euleptorhamphus viridis

Ribbon Halfbeak, Euleptorhamphus viridis. Fish provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, August 2011. Length: 43 cm (17 inches).

The Ribbon Halfbeak, Euleptorhamphus viridis, is a member of the Halfbeak or Hamiramphidae Family, and is known in Mexico as agujeta alargada. Globally, there are two species in the genus Euleptorhamphus, one of which is found in Mexican waters, the species described herein, found in the Pacific Ocean.

The Ribbon Halfbeaks has an extremely elongated compressed ribbon-like body. They have a silvery appearance with a greenish-blue back and transparent fins. Their lower jaw extends into an elongated beak and their upper jaw is short and triangular. They have small teeth set in bands. Their anal fin does not have spines and has 20 to 25 rays and originates behind the dorsal fin; their caudal fin is deeply forked with the lower lobe being larger than the upper lobe; their dorsal fin does not have spines and has 20 to 25 rays; their pectoral fins are exceedingly long; and, their pelvic fins are on the abdomen well back on the body. Their anal and dorsal fins have slightly raised front lobes and are well back on the body with bases opposite each other. They have 25 to 32 gill rakers. They are covered with small scales and their lateral line is low on the body.

The Ribbon Halfbeak is a pelagic species normally found in coastal waters on the surface to depths up to 6 m (20 feet). They are one of the largest Halfbeaks in the Tropical Eastern Pacific reaching a maximum of 53 cm (21 inches) in length. They feed on small fish and plankton. In turn they are preyed upon by birds, dolphins, dorado, marlins, porpoises, squids, and tuna. Reproduction is oviparous with females releasing large eggs containing a sticky substance that allows the eggs to attach to floating debris. The Ribbon Halfbeak is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Ribbon Halfbeak is a resident of all Mexican waters of the Pacific Ocean with the exception that they are absent from of the northern 40% of the Sea of Cortez and from along the extreme northwest coast of Baja.

The Ribbon Halfbeak cannot be confused with any other species due to the body depth.

From a conservation perspective the Ribbon Halfbeak has not been formally evaluated. They are relatively small in stature, seldom seen by humans, and are of limited interest to most.