Hemiramphus

Hemiramphus is a genus of ray‑finned fishes in the family Hemiramphidae, commonly known as halfbeaks. The genus contains about sixteen described species, including Hemiramphus brasiliensis, Hemiramphus brasilius, and Hemiramphus lesliei. Members of this genus are distributed throughout tropical and subtropical oceans worldwide, occurring in both coastal estuaries and open marine environments up to the edge of the continental shelf.

Halfbeaks possess a distinctive elongated, laterally compressed body with a markedly shortened upper jaw and a long, lower jaw. The dorsal fin is located near the middle of the back, and the caudal fin is forked, providing efficient swimming capabilities. Their scales are generally small, and juveniles often exhibit a silver coloration that darkens in adults. Most species reach lengths between 15 and 30 centimeters, although some can exceed 35 centimeters.

Hemiramphus species feed primarily on plankton, small invertebrates, and occasionally fish eggs. They are known for their schooling behavior, forming large aggregations that can become an important forage species for larger pelagic predators. Some species, such as Hemiramphus brasiliensis, are occasionally caught by artisanal and commercial fisheries, but they are not considered a major commercial target. The genus is also of interest for aquaculture research due to their rapid growth and tolerance of a range of salinities.

The taxonomy of Hemiramphus has undergone revisions as molecular phylogenetics has clarified relationships within Hemiramphidae. Current studies suggest that several nominal species may be cryptic or represent local variations of a broader species complex. Ongoing research continues to refine species boundaries and understand the ecological roles of these fishes in coastal ecosystems.