Esociformes |
![Northern pike (Esox lucius)](./modules/Fish-MM/images/250px-Esox_lucius1.jpg)
Northern pike (Esox lucius)
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Scientific classification |
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Families |
Esocidae (pikes)
Umbridae (mudminnows) |
Esociformes is a small order of
ray-finned fish, with two families, the Umbridae (mudminnows)
and the Esocidae (pikes). The pikes of genus
Esox give the order its name. There are ten
species--five in each family.
This order is closely related to the Salmoniformes, the
two comprising the superorder Protacanthopterygii, and are
often included in their order. The esociform fishes first
appeared in the mid-Cretaceous -- early products of the
Euteleost radiation of that time. Today they are found only
in fresh water in North America and the northern Eurasian regions.
Pikes
The pikes tend to be lie-in-wait, ambush
predators, with elongated snouts, long, well-muscled
torsos, forked tails, and dorsal and anal fins set well back
and opposite each other for rapid acceleration along a
straight line, allowing the fish to quickly emerge from
cover to capture its prey. Prey capture is facilitated by
the impaling of the prey animal on the sharp teeth, after
which the pike retreats to cover, turns the prey around, and
swallows it, head first.
Anatomically, the pikes are characterized by the presence
of shark-like, maxillary teeth, a mesocoracoid, and the
absence of an
adipose fin, breeding tubercules, and pyloric cecae.
The two more prominent species of Escoformidae are
Esox lucius, or the northern pike, a popular sport fish
that may reach lengths as great as a meter and a half, and
the "muskie," E. masquinongy, which grows even
larger.
Mudminnows
Mudminnows are much smaller than their pike cousins, with
usual lengths of less than 20 cm. However, they are also
extremely efficient, lie-in-wait, ambush predators, feeding
mostly on the sorts of invertebrates commonly found in warm
backwaters. Of the three North American species of genus
Umbra, one, U. limi, possesses a limited
capability for air breathing. Umbra spp. are most
commonly found in the Atlantic coast regions of North
America, along the marshy, low-oxygen areas of the
Mississippi River, and in similar environments in Europe.
References
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"Esociformes".
FishBase. Ed. Ranier Froese and Daniel Pauly.
October 2004 version. N.p.: FishBase, 2004.
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Esociformes (TSN 553131).
Integrated Taxonomic Information System. Accessed on 8
December 2004