'Amphibious fish' are
fish that are able to leave water for extended periods of time. About 11 distantly related
genera of fish are considered amphibious. This suggests that many fish genera independently
evolved amphibious traits. These fish use a range of terrestrial
locomotory modes, such as
lateral undulation,
tripod-like walking (using paired
fins and
tail), and jumping. Many of these locomotory modes incorporate multiple combinations of
pectoral,
pelvic and tail fin movement.
[1]
Many ancient fish had
lung-like
organs, and a few, such as the
lungfish, still do. Some of these ancient "lunged" fish were the
ancestors of modern amphibians. However, in most recent fish
species these organs evolved into the
swim bladders, which help control
buoyancy. Having no lung-like organs, modern amphibious fish and also many fish in
oxygen poor water, use other methods such as their
gills or their
skin to breathe air. Amphibious fish may also have
eyes adapted to allow them to see clearly in air, despite the
density differences between air and water.
[2]
List of amphibious fish
Lung breathers
★ Various "lunged" fish:. These are now
extinct. A few of this group were ancestors of the
basal tetrapods that led to all
tetrapods:
amphibians,
reptiles,
birds, and
mammals.
★
Lungfish (''Dipnoi''): Six species, have
limb like fins, and can breathe air. Some are
obligate air breathers. Some species will bury in the mud when the body of water they live in dries up, surviving up to two years until water returns.
Gill or skin breathers
★
Rockskippers: These are found in
Panama. These fish come onto land to catch prey and escape aquatic
predators. They often come out of water for up to 20 minutes.
★
Wooly sculpin: Found in tide pools along the
Pacific coast, these fish will leave water if the oxygen levels get low and can breathe air for 24 hours.
★
Mudskippers (
Oxudercinae): This subfamily of
gobies is probably the most land adapted of fish. Mudskippers are found in
mangrove swamps in
Africa and the
Indo-Pacific, they frequently come onto land and can survive in air for up to three and a half days
[3]. Mudskippers breathe through their skin and also through the lining of the mouth (the
mucosa) and throat (the
pharynx). This requires the mudskipper to be wet, limiting mudskippers to humid habitats. This mode of breathing, similar to that employed by amphibians, is known as cutaneous breathing. They propel themselves over land on their sturdy forefins.
★
Anableps: Found in
Central and
South America, the unusual "four-eyed" and "four-
sexed" fish can move on land for short periods of a time. Its pupils are divided into two. The upper half is adapted to see in air, and the lower half is for seeing in water.
★
Eels: Some eels, such as the
European eel and the
American eel, can live for an extended time out of water and can crawl on land if the soil is moist.
★
Snakehead fish (
Channidae): This family of fish are obligate air breathers, breathing air using their
suprabranchial organ, which is a primitive
labyrinth organ. The
Northern Snakehead has a limited capacity to wriggle over wet grass and mud.
★
Airbreathing catfish (
Clariidae). This family of fish has a labyrinth organ which allows them to breathe air. Some species from this group can "walk" on land. For example the
Walking catfish (''Clarias batrachus'') of
Southeast Asia, can "walk" on land by wriggling and using its pectoral fins, this allows it to move between the slow-moving, and often stagnant and temporary bodies of water in which it lives. Another amphibious species of this family is the
Eel catfish (''
Channallabes apus''), which lives in swamps in Africa, and known to hunt beetles on land
[4].
★
Labyrinth fish (
Anabantoidei). This suborder of fish also use also use a labyrinth organ to breathe air. Some species from this group can move on land. An amphibious fish from this family is the
Climbing gourami, an African and Southeast Asian fish that is capable of moving from pool to pool over land by using its
pectoral fins,
caudal peduncle and gill covers as a means of locomotion. It is said that climbing gourami move at night in groups.
See Also
★
Walking fish