The Halfbeaks Fish

Fish World | The Halfbeaks Fish | The halfbeaks (Hemiramphidae family) is a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The family is divided into two subfamilies Hemiramphidae, the first naval Hemiramphinae and freshwater or estuarine Zenarchopterinae. The halfbeaks are named for their prominent jaws, where the lower jaw are considerably longer than the upper jaw. The halfbeaks show an exceptionally wide range of reproductive modes. These include leg, and ovoviviparity true vivipary where the mother is connected to the developing embryos through a placenta-like structure. Some of the viviparous species, developing embryos are also known to oophagy or intrauterine cannibalism, where the developing embryos feed on eggs or embryos in the womb show.

Although not commercially important themselves, they feed fish to support artisanal fisheries and local markets worldwide. They are also fed by other commercially important predators, such as billfishes, mackerels, and sharks. Some halfbeaks be maintained as aquarium fish.

In 1775, Carolus Linnaeus was the first to scientifically describe a halfbeak, Esox brasiliensis. In 1775 Peter Forsskål two more species described as Esox, Esox far and Esox marginatus. It was not until 1816 that Georges Cuvier sex Hemiramphus made, from that moment, all three were classified as Hemiramphus. In 1859, Gill established Hemiramphidae, deriving its name from Hemiramphus, type genus of the family. The name comes from the Greek hemi meaning half and rhamphos, meaning beak or bill.
The family Hemiramphidae is currently divided into two subfamilies, and the Hemiramphinae Zenarchopterinae, each about half the known species. A 2004 revision of the family recognized two subfamilies, 13 genera and 117 species and subspecies. More recently, the family Hemiramphidae Oxyporhamphus much Exocoetidae.

The Hemiramphinae are primarily marine and found in the Atlantic, Pacific and Indian Oceans, although some live in estuaries and rivers. The Zenarchopterinae are limited to the Indo-West Pacific zoogeographic region, an area that runs from East Africa to the Caroline Islands. Zenarchopterinaeexhibit the strong sexual dimorphism, practicing internal fertilization, and in some cases ovoviviparous or viviparous. Three genera of this subfamily are exclusively freshwater fish and some, such as wrestling halfbeak, have become commonly traded aquarium fish. Some authors recognize Zenarchopterinae as a separate family (Zenarchopteridae).
On the one hand, there is little doubt that they are most closely related to three other families of sleek, surface-water fish, the flying fishes, fishes needle, and Sauries. Traditionally, these four families have taken up the order Beloniformes. The halfbeaks and flying fishes are considered as a group, the superfamily Exocoetoidea, and the needle fishes and Sauries another, the superfamily Scomberesocoidea form.

On the other hand, recent studies have shown that instead of forming a monophyletic group (a clade), actually the family halfbeak some lines to the ancestral fishes and flying fishes include the needle. In other words, as traditionally defined, is paraphyletic halfbeak family.

Within the subfamily Hemiramphinae, the "flying halfbeak" genus Oxyporhamphus proved to be particularly problematic, but morphologically closer to the flying fishes, molecular evidence and place it with Hemiramphus Euleptorhamphus. Together these three genera form the sister group to the flying fish family. The other two genera hemiramphine Hyporhamphus Arrhamphus and form a clade of other less obvious placement.
Rather closely related to the flying fishes, the subfamily Zenarchopterinae seems to be the sister group of the needle and fishes Sauries. This is based on the pharyngeal jaw apparatus, sperm ultrastructure, and molecular evidence. However, this hypothesis is difficult implications for how the morphological evolution of the group is understood as the combined pharyngeal plate is considered a reliable diagnosis of halfbeak family. Moreover, the existing theory that because young garfish pass a development which the lower jaw is longer than the upper jaw (called "halfbeak stage"), the theory that halfbeaks paedomorphic needlefish are unsustainable.  

In fact, the unequal length of the upper and lower jaw seems halfbeaks the basal condition, with garfish relatively derived in comparison with The halfbeaks are elongated, streamlined fish adapted to life in open water. Halfbeaks range in size from 4 cm (1.6 in) standard length (SL) in Hemirhamphodon Tengah to more than 40 centimeters (16 in) SL in the case of Euleptorhampus viridis. The scales are relatively large, cycloid (smooth), and easily. There are no spines in the fins. A distinguishing feature is that the third pair of upper pharyngeal bones are anklylosed (melted) in a plate. Halfbeaks are one of the many fish families that lack a stomach, all with a pharyngeal jaw apparatus (pharyngeal mill).  Most species have a longer lower jaw, just as young, but this feature is lost when the fish mature, like Chriodorus, for example.

As usual for surface dwelling, open water fishing, most species are silvery, darker above and lighter below, an example of counter shading. The tip of the mandible is bright red or orange in most species. Small colored spots, especially among men, can only be found on the fins and the tip of the beak.

Halfbeaks wear different adaptations to feed on the surface. The eyes and nostrils are at the top of the head and upper jaw is mobile, but not the lower jaw. Combined with its streamlined shape and concentration of the fins to the back (similar to that of a pike), these adjustments allow halfbeaks to locate, catch, swallow food and very effective.

Sexual dimorphism is apparent in some species. Males of the species vivaparous ovovivaparous and all have a custom anal fin, the androgen stage, similar to the gonopodium of poecilid livebearers, used to deliver sperm to the females. Although most spawning species mate by the divestiture of the spleen externally, as is characteristic of bony fish, at least some practice internal fertilization: male Zenarchopterus a modified anal fin used to direct sperm into the genital opening of the female just before spawning .

In addition to changes in the anal fin, other differences include size, color, and beak length or shape. Normorhamphus female are much larger than the males, but not as brightly colored and have shorter beaks. By contrast, male Hemirhamphodon are larger than females, and some species, such as Hemirhamphodon pogonognathus, a long beard-like brush on the end of the beak Marine halfbeaks are omnivorous feeding on algae, marine plants such as seagrasses, plankton, invertebrates such as pteropods and crustaceans and small fish. Some subtropical species at least, people are more rapacious than adults. Some tropical species that feed on plants and animals during the day at night, while other species alternately herbivory and carnivory in summer in winter. They are in turn eaten by many ecologically and commercially important fish such as billfish, mackerel, and sharks, and are therefore an important link between trophic levels.

Freshwater species are more predatory than the marine species, and typically orient themselves in the present and to participate in aquatic insect larvae such as mosquito larvae and small insects such as flies that have fallen on the surface of the water, especially mosquitoes and spiders.

Halfbeaks exhibit a remarkably wide range of reproductive modes, ranging from simple laying (oviparity) to various forms of viviparous (ovoviviparity and viviparity). There is a taxonomic division in this one: all Hemiramphinae are egg-layers, while many of the ovoviviparous or viviparous are either Zenarchopterinae.