Xenentodon cancila
Encyclopedia
The freshwater garfish, Xenentodon cancila is the sole member of its genus
. It is found primarily in freshwater
habitat
s, though it is sometimes found in brackish water and the sea. It is most common in rivers, but may also be found pond
s, canals, and other freshwater habitats. It is the only member
of the genus Xenentodon.
fish Xenentodon cancila, has been traded under a variety of common names, including needlefish, silver needlefish, Asian freshwater needlefish, needlenose halfbeak, freshwater gar, and numerous others. While belonging to the same family as the marine needlefish known in Europe as gar or garpike, Belone belone, these fish are of course much more distantly related to other fishes sometimes called gars (such as the North American Lepisosteidae and South American pike characin
s).
from India
and Sri Lanka
to the Malaysian Peninsula.
exists, the male fish often having anal and dorsal fins with a black edge.
tend to describe this fish as a predator that eats animals such as fish
and frog
s, its natural diet appears to consist almost entirely of crustacean
s.
are almost 12 mm long. At this point they will eat small live foods including week-old labyrinth fish.
and are also traded as aquarium fish.
. It has been kept by European aquarists since 1910, and was first bred in captivity at the Biological Station Wilhelminenberg, Austria
in 1963. Xenentodon cancila is generally considered quite a difficult species to maintain because of its large size, nervous behaviour, and preference for live foods. Alongside misunderstandings of the natural diet of these fish, there has been confusion over the optimal water conditions required by this species when kept in home aquaria, with the addition of salt to the water often being recommended. In fact these fish do perfectly well in freshwater aquaria.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
. It is found primarily in freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...
s, though it is sometimes found in brackish water and the sea. It is most common in rivers, but may also be found pond
Pond
A pond is a body of standing water, either natural or man-made, that is usually smaller than a lake. A wide variety of man-made bodies of water are classified as ponds, including water gardens, water features and koi ponds; all designed for aesthetic ornamentation as landscape or architectural...
s, canals, and other freshwater habitats. It is the only member
Monotypic
In biology, a monotypic taxon is a taxonomic group with only one biological type. The term's usage differs slightly between botany and zoology. The term monotypic has a separate use in conservation biology, monotypic habitat, regarding species habitat conversion eliminating biodiversity and...
of the genus Xenentodon.
Common names
As a reasonably popular aquariumAquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
fish Xenentodon cancila, has been traded under a variety of common names, including needlefish, silver needlefish, Asian freshwater needlefish, needlenose halfbeak, freshwater gar, and numerous others. While belonging to the same family as the marine needlefish known in Europe as gar or garpike, Belone belone, these fish are of course much more distantly related to other fishes sometimes called gars (such as the North American Lepisosteidae and South American pike characin
Ctenoluciidae
Ctenoluciidae , also known as pike-characins, is a small family of freshwater fishes from Panama and South America.They have elongate, pike-like bodies, and several sharp and conical teeth...
s).
Distribution
The freshwater garfish is widely distributed across South and Southeast AsiaSoutheast Asia
Southeast Asia, South-East Asia, South East Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China, east of India, west of New Guinea and north of Australia. The region lies on the intersection of geological plates, with heavy seismic...
from India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
and Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
to the Malaysian Peninsula.
Morphology
In common with other needlefish, this species has an elongate body with long, beak-like jaws filled with teeth. The dorsal and anal fins are positioned far back along the body close to the tail. The body is silvery-green, darker above and lighter below with a dark band running horizontally along the flank. Slight sexual dimorphismSexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
exists, the male fish often having anal and dorsal fins with a black edge.
Diet
While aquarium booksFishkeeping
Fishkeeping is a popular hobby concerned with keeping fish in a home aquarium or garden pond. There is also a fishkeeping industry, as a branch of agriculture.-Types of fishkeeping systems:...
tend to describe this fish as a predator that eats animals such as fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and frog
Frog
Frogs are amphibians in the order Anura , formerly referred to as Salientia . Most frogs are characterized by a short body, webbed digits , protruding eyes and the absence of a tail...
s, its natural diet appears to consist almost entirely of crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s.
Reproduction
This species is oviparous. In aquaria at least, spawning takes place in the morning, with small numbers of eggs being deposited among plants. The eggs are about 3.5 mm in diameter and are attached to plant leaves with sticky threads about 20 mm long. The eggs take ten days to hatch, at which point the frySpawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
are almost 12 mm long. At this point they will eat small live foods including week-old labyrinth fish.
Human significance
Freshwater needlefish support minor fisheriesFishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
and are also traded as aquarium fish.
In the aquarium
The freshwater garfish is one of a handful of needlefish species kept in public and home aquariaAquarium
An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...
. It has been kept by European aquarists since 1910, and was first bred in captivity at the Biological Station Wilhelminenberg, Austria
Austria
Austria , officially the Republic of Austria , is a landlocked country of roughly 8.4 million people in Central Europe. It is bordered by the Czech Republic and Germany to the north, Slovakia and Hungary to the east, Slovenia and Italy to the south, and Switzerland and Liechtenstein to the...
in 1963. Xenentodon cancila is generally considered quite a difficult species to maintain because of its large size, nervous behaviour, and preference for live foods. Alongside misunderstandings of the natural diet of these fish, there has been confusion over the optimal water conditions required by this species when kept in home aquaria, with the addition of salt to the water often being recommended. In fact these fish do perfectly well in freshwater aquaria.