Four-eyed fish

Four-eyed fish

Taxobox
name = Four-eyed fishes



image_width = 240px
image_caption = "Anableps" sp.
regnum = Animalia
phylum = Chordata
classis = Actinopterygii
ordo = Cyprinodontiformes
familia = Anablepidae
genus = "Anableps"
genus_authority = Scopoli, 1777
binomial = "Anableps anableps"
binomial_authority = (Linnaeus, 1758)
binomial2 = "Anableps dowei"
binomial2_authority = Gill, 1861
binomial3 = "Anableps microlepis"
binomial3_authority = Müller & Troschel, 1844
The four-eyed fishes are a genus, "Anableps", of fishes in the family Anablepidae. They have eyes raised above the top of the head and divided in two different parts, so that they can see below and above the water surface at the same time. Like their relatives, the onesided livebearers, four eyed fishes only mate on one side, right-"handed" males with left-"handed" females and vice versa. These fish inhabitat freshwater and brackishwater and are only rarely coastal marine. They originate from lowlands in southern Mexico to Honduras and northern South America.cite book | title = Fishes of the World | last = Nelson | first = Joseph, S. | publisher = John Wiley & Sons, Inc. | year = 2006 | id = ISBN 0471250317]

Behavior

These fish spend most of their time at the surface of the water. Their diet mostly consists of terrestrial insects which are readily available at the surface, however they may consume other foods such as other invertebrates, diatoms, and small fishes.Fishbase species | genus = Anableps | species = anableps | year = 2007 | month = Mar]

These fish will group differently depending on the species. "A. anableps" commonly congegrates in schools. "A. microlepis" also is gregarious, but restricts its schools to about a dozen individuals; it is also recorded to be found singly or as couples.Fishbase species | genus = Anableps | species = microlepis | year = 2007 | month = Mar]

"A. anableps" is also known for the ability to survive out of water exposed to air, such as during low tide.

Physical characteristics

The maximum length of these species is up to 32 cm TL in "A. microlepis", making this species the largest in the order Cyprinidontiformes.

Reproductive organs

These fish are one-sided livebearers and their reproductive organs are unique to its subfamily. This characteristic is only shared with the related genus "Jenynsia".

Eye

The four-eyed fishes only have two eyes each, but the eyes are specially adapted for their surface-dwelling lifestyle. The eyes are positioned on the top of the head, and the fish floats at the water surface with only the lower half of each eye underwater. The two halves are divided by a band of tissue and the eye has two pupils, connected by part of the iris. The upper half of the eye is adapted for vision in air, the lower half for vision in water. The lens of the eye also changes in thickness top to bottom to account for the difference in the refractive indices of air versus water.

Relationship to humans

Four-eyed fish are often used in eye research.Fishbase species | genus = Anableps | species = dowei | year = 2007 | month = Mar]

This fish is occasionally found in pet stores.

References

General References

*
*


Wikimedia Foundation. 2010.

Игры ⚽ Поможем написать реферат

Look at other dictionaries:

  • four-eyed fish — noun : a fish of the genus Anableps * * * a small, surface swimming fish, Anableps anableps, inhabiting shallow, muddy streams of Mexico and Central America, having each eye divided, with the upper half adapted for seeing in air and the lower… …   Useful english dictionary

  • four-eyed fish — brazilinė keturakė statusas T sritis zoologija | vardynas taksono rangas rūšis atitikmenys: lot. Anableps anables angl. four eyed fish rus. бразильская четырёхглазка ryšiai: platesnis terminas – keturakės …   Žuvų pavadinimų žodynas

  • four-eyed fish — a small, surface swimming fish, Anableps anableps, inhabiting shallow, muddy streams of Mexico and Central America, having each eye divided, with the upper half adapted for seeing in air and the lower half for seeing in water. Also, foureye fish… …   Universalium

  • four-eyed fish — noun A genus Anableps of fish in the family Anablepidae having eyes raised above the top of the head and divided in two different parts, so that they can see below and above the water surface at the same time …   Wiktionary

  • Four-eyed — may refer to:In mammalogy:* Anderson s Four eyed Opossum, opossum species from South America * Brown Four eyed Opossum, pouchless marsupial of the family Didelphidae * Gray and black four eyed opossum, members of the Didelphimorphia order * Gray… …   Wikipedia

  • four-eyed butterfly fish — keturakis jūrų drugelis statusas T sritis zoologija | vardynas taksono rangas rūšis atitikmenys: lot. Chaetodon capistratus angl. four eyed butterfly fish rus. хетодон ryšiai: platesnis terminas – jūrų drugeliai …   Žuvų pavadinimų žodynas

  • four-eyedfish — four eyed fish n. Either of two freshwater fishes (Anableps anableps or A. microlepis) of tropical America, having bulging eyes divided horizontally, with the upper part adapted for vision above the water and the lower part for vision below the… …   Universalium

  • four-eyes — ˈ ̷ ̷ˌ ̷ ̷ noun plural but singular in construction 1. : four eyed fish 2. : a person who wears glasses * * * /fawr uyz , fohr /, n., pl. four eyes. 1. Facetious or Disparaging. a person who wears eyeglasses. 2. See four eyed fish. [ …   Useful english dictionary

  • four-eyes — /fawr uyz , fohr /, n., pl. four eyes. 1. Facetious or Disparaging. a person who wears eyeglasses. 2. See four eyed fish. [1870 75] * * * …   Universalium

  • Diversity of fish — Fish come in many shapes and sizes. This is a sea dragon, a close relative of the seahorse. They are camouflaged to look like floating seaweed.[1][2][3] …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”