viviparous halfbeak
Zenarchopteridae, the viviparous halfbeaks, is a family in the order Beloniformes. The Zenarchopteridae exhibit strong sexual dimorphism, practicing internal fertilisation, and in some cases ovoviviparous or viviparous (the family also includes ...
s. They are widely distributed in fresh and
brackish
Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt water) and fresh water together, as in estuari ...
water in South and Southeast Asia, ranging from India to the
Philippines
The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no),
* bik, Republika kan Filipinas
* ceb, Republika sa Pilipinas
* cbk, República de Filipinas
* hil, Republ ...
and
Greater Sundas
The Greater Sunda Islands (Indonesian and Malay: ''Kepulauan Sunda Besar'') are four tropical islands situated within Indonesian Archipelago, in the Pacific Ocean. The islands, Borneo, Java, Sulawesi and Sumatra, are internationally recognised fo ...
. They are all
viviparous
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...
, producing small clutches of up to 30 fry that closely resemble the adults, except they are much smaller, around in length. Adults are typically around in length, with females being slightly larger than males. Males tend to be more brightly coloured and are well known for being aggressive towards one another. The
wrestling halfbeak
The wrestling halfbeak (''Dermogenys pusilla'') also known as Malayan halfbeak is a species of viviparous halfbeak native to the fresh and brackish waters of rivers and coastal regions in South-East Asia, in Singapore, Thailand, Indonesia, Thaila ...
, ''D. pusilla'', is widely used in Asia as fighting animals upon which wagers are placed (see Siamese fighting fish). Both sexes have lower jaws (mandibles) that are much longer than the upper ones, and from this comes the "halfbeak" name.
''Dermogenys'' feed extensively on small insects, either in the form of aquatic
larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle.
The ...
e or as flying insects that have fallen onto the surface of the water. They are important predators on insects such as mosquitoes, so play a role in controlling
malaria
Malaria is a mosquito-borne infectious disease that affects humans and other animals. Malaria causes symptoms that typically include fever, tiredness, vomiting, and headaches. In severe cases, it can cause jaundice, seizures, coma, or death. S ...
.
Reproduction
''Dermogenys'' are live-bearing fish that practise internal fertilisation. The male is equipped with a gonopodium-like anal fin known as an andropodium that delivers sperm into the female. The
gestation
Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregna ...
period is about one month. The exact mode of reproduction ranges from
ovoviviparity
Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a term used as a "bridging" form of reproduction between egg-laying oviparous and live-bearing viviparous reproduction. Ovoviviparous animals possess embryos that develop insi ...
through to
viviparity
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...
(see section on reproduction in the
Zenarchopteridae
Zenarchopteridae, the viviparous halfbeaks, is a family in the order Beloniformes. The Zenarchopteridae exhibit strong sexual dimorphism, practicing internal fertilisation, and in some cases ovoviviparous or viviparous (the family also includes ...
article). About ten embryos are developed at any one time, but at birth, these are fairly large (around ) compared with other fish of this size. ''Dermogenys'' adults are around in length, depending on the species.
Kuhl
KUHL (1440 AM broadcasting, AM) is a commercial radio station that is City of license, licensed to Santa Maria, California and serves the Santa Maria, California, Santa Maria—Lompoc, California area. The station is owned by Knight Broadcasting ...
Bleeker Bleeker is a Dutch occupational surname. Bleeker is an old spelling of ''(linnen)bleker'' ("linen bleacher").Dermogenys vogti'' Brembach, 1982
See also
*
Halfbeak
Hemiramphidae is a family of fishes that are commonly called halfbeaks, spipe fish or spipefish. They are a geographically widespread and numerically abundant family of epipelagic fish inhabiting warm waters around the world. The halfbeaks are ...