Lungfish - The fish time forgot
William Berg
Lungfish are ancient fish that can be found in Australia, South
America and Africa. The group lungfish contains only a few
species and no more than a total of six species are known. This
six species can be divided into two different families. One
family, Lepidosirenidae, contain five species found in South
America and Africa. The other family is called Ceratodidae ad
contains only one species, the Australian lungfish.
All lungfish share the one common organ that has given them their
name. They have developed lungs which allows for them to survive
in water with very low oxygen levels where other fish can't
survive. The lungs also allow them to survive out of the water.
The lungs found in lungfish are very similar to the lungs found
in primitive reptiles.
Lungfish has been present since the Lower Devonian area which
means that they have been around for more than 100 million years.
The number of species used to be much more numerous in the past
but all but six species are now extinct.
Lungfish are easily recognized on how they look. They have
primitive looking snakelike bodies. All lungfish species can grow
very big and the African lungfish can grow to be more than 2m / 6
feet long.
They are highly predatory species that eats or try to eat
everything that fits into their large mouths. (Including aquarium
decoration and heaters) Their natural diet consists of
fish, crabs, crayfish and anything else they might find.
The Lepidosirenidae family of lungfish can survive in very little
water and the African lungfish can survive without water for up
to two years. South American lungfish survives low water levels
by digging a hole in the bottom mud where they build a nest. They
then wait in the nest until the water returns. The African
Lungfish is an even better survivor. They don't settle for
building a nest but also cover their bodies with a secretion.
This secretion forms a leather like cocoon that helps keep the
lungfish moist until the water returns. They hibernate during the
time they wait for the water to return and can as earlier
mentioned survive in tried out desert like areas for up to two
years or perhaps longer.
The Australian lungfish doesn't hibernate like some other
lungfishes. This makes them dependent on water but can be found
and survive in very small water bodies.
All Lepidosirenidae lungfish species builds some type of nest in
which they deposit their eggs. The male guards the eggs until
they hatch. The Australian lungfish doesn't build any nest. They
just deposit the eggs on the bottom within their habitats.
This was just a short introduction to lungfish. Read more about
Lungfish. Another fascinating group of fishes you can read more
about is Tilapia http://www.tilapia.ws/