Xenentodon cancila

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Needle Nose Gar
Scientific classification
Kingdom: Animalia Phylum: Chordata Class: Actinopterygii Order: Beloniformes Family: Belonidae Genus: Xenentodon Species: X. cancila
Binomial name
Needle Nose Gar-Xenentodon cancila (Hamilton, 1822)
Synonyms
Belone cancila Hamilton, 1882 Esox cancila Hamilton, 1882

The freshwater garfish, Xenentodon cancila is the sole member of its genus. It is found primarily in freshwater habitats,^[1] though it is sometimes found in brackish water and the sea.^[1] It is most common in rivers, but may also be found ponds, canals, and other freshwater habitats.^[1]

Contents 1 Common names 2 Distribution 3 Morphology 4 Diet 5 Reproduction 6 Human significance 6.1 In the aquarium 6.2 As a dangerous animal 7 References

[edit] Common names

As a reasonably popular aquarium fish Xenentodon cancila, has been traded under a variety of common names, including needlefish,^[2] silver needlefish^[3], Asian freshwater needlefish,^[2] needlenose halfbeak,^[4] freshwater gar,^[4] and numerous others. While belonging to the same family as the marine needlefish known in Europe as gar or garpike, Belone belone,^[5] 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 characins).^[4]

[edit] Distribution

The freshwater garfish is widely distributed across South and Southeast Asia from India and Sri Lanka to the Malaysian Peninsula.^[3]

[edit] Morphology

In common with other needlefish, this species has an elongate body with long, beak-like jaws filled with teeth.^[5] The dorsal and anal fins are positioned far back along the body close to the tail.^[5] The body is silvery-green, darker above and lighter below with a dark band running horizontally along the flank.^[1] Slight sexual dimorphism exists, the male fish often having anal and dorsal fins with a black edge.^[5][3]

[edit] Diet

While aquarium books tend to describe this fish as a predator that eats animals such as fish and frogs,^[3] its natural diet appears to consist almost entirely of crustaceans.^[3]

[edit] Reproduction

This species is oviparous.^[3] In aquaria at least, spawning takes place in the morning,^[3] with small numbers of eggs being deposited among plants.^[3] The eggs are about 3.5 mm in diameter and are attached to plant leaves with sticky threads about 20 mm long.^[3] The eggs take ten days to hatch, at which point the fry are almost 12 mm long.^[3] At this point they will eat small live foods including week-old labyrinth fish.^[3]

[edit] Human significance

Freshwater needlefish support minor fisheries and are also traded as aquarium fish.^[1]

[edit] In the aquarium

The freshwater garfish is one of a handful of needlefish species kept in public and home aquaria.^[5] It has been kept by European aquarists since 1910,^[5] and was first bred in captivity at the Biological Station Wilhelminenberg, Austria in 1963.^[3] Xenentodon cancila is generally considered quite a difficult species to maintain because of its large size, nervous behaviour, and preference for live foods.^[2] Alongside misunderstandings of the natural diet of these fish,^[6] 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.^[4] In fact these fish do perfectly well in freshwater aquaria.^[6]

[edit] As a dangerous animal

Xenentodon cancila has been said to be able to launch itself out of the water with such force that it can kill a human, though some ichthyologists say that this is unlikely.^[1] They are certainly capable of biting.^[1]

[edit] References