Needlefish

From Wikipedia, the free encyclopedia

For other uses, see Needlefish (disambiguation).

iNeedlefishes

Tylosurus crocodilus

Scientific classification

Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Beloniformes
Family:	Belonidae

Genera

Ablennes
Belone
Lhotskia
Platybelone
Potamorrhaphis
Pseudotylosurus
Stenocaulis
Strongylura
Thalassosteus
Tylosurus
Xenentodon

Needlefishes (family Belonidae) are piscivorous fishes primarily associated with shallow marine habitats or the surface of the open sea. Some genera include species found in marine, brackish, and freshwater environments (e.g., Strongylura) while at a few genera are confined to freshwater rivers and streams, including Belonion, Potamorrhaphis, and Xenentodon. <ref>Froese, R. and D. Pauly. Editors.. 207 Family Belonidae - Needlefishes. FishBase. Retrieved on 2006-11-29.</ref> Needlefish closely resemble North American freshwater gars (family Lepisosteidae) in being elongate and having long, narrow jaws filled with sharp teeth, and some species of needlefish are referred to as gars or garfish despite being only distantly related to the true gars. In fact the name "garfish" was originally used for the needlefish Belone belone in Europe and only later applied to the North American fishes by European settlers during the 18th Century.<ref>Douglas Harper. Online Etymological Dictionary. Online Etymological Dictionary. Retrieved on 2006-11-29.</ref> Needlefish are in fact members of the Beloniformes and therefore most closely related to flying fish, sauries, and halfbeaks.

1 Phylogeny
2 Ecology
3 In the aquarium
4 References
5 External links

[edit] Phylogeny

Needlefishes are members of the Beloniformes and close relatives of the flyingfishes, halfbeaks, and sauries. <ref>Helfman G., Collette B., & Facey D.: The Diversity of Fishes, Blackwell Publishing, pp 274-276, 1997, ISBN 0865422567</ref> However, the precise relationships between these groups has been debated among systematists. Juvenile needlefish pass through a developmental stage where the lower jaw is longer than the upper jaw, sometimes known as the "halfbeak stage", so it has been hypothesised that halfbeaks are paedomorphic needlefish, that is, halfbeaks as adults retain characteristics of the juvenile stages of their ancestors, the needlefish. <ref> Lovejoy, N, Iranpour, M & Collette, B: Phylogeny and Jaw Ontogeny of Beloniform Fishes. Integrative and Comparative Biology 44, pp 366-377, 2004 [1]</ref> The alternate view is that the unequal lengths of the upper and lower jaws seen in halfbeaks is the basal condition, with needlefish being relatively derived in comparison. <ref> Boughton, D, Collette, B, & McCune, A.: Heterochrony in Jaw Morphology of Needlefishes (Teleostei: Belonidae). Systematic Zoology 40, pp 329-352, 1991</ref>

[edit] Ecology

All needlefish feed primarily on smaller fishes, which they catch with a sideways sweep of the head. In addition some species will also take plankton, swimming crustaceans, and small cephalopods. Freshwater species are also predatory, with the Asian species at least feeding exclusively on small crustaceans. <ref>Froese, R. and D. Pauly. Editors.. Species Summary for Xenentodon cancila . FishBase. Retrieved on 2006-11-29.</ref>

Needlefish are most common in the tropics but some inhabit temperate waters as well, particularly during the summer months. Belone belone is a common North Atlantic species that often swims in schools alongside mackerel and typically grows to around 60 cm in length. It is easily caught with a baited hook, and is considered a good food fish despite having bright green bones.

Image:Belonidae tring museum.JPG

[edit] In the aquarium

Some species of needlefish inhabit brackish and freshwater environments, and one of the freshwater species, Xenentodon cancila from South East Asia, is occasionally kept as an aquarium fish. It is a relatively small species, no more than 30 to 40 cm in length when fully grown, but is considered to be a rather delicate fish best suited to advanced aquarists.<ref>Monks N: Straight to the point: the Beloniformes. Practical Fishkeeping, October 2005</ref>