Last updated on April 16, 2014 at 17:34 EDT

Queensland lungfish

The Queensland lungfish, Neoceratodus forsteri, also known as Burnett salmon and Barramunda, is the sole member of the family Ceratodontidae, and one of the only six lungfish species that remain. Olive or dull brown in color, it grows to about 59.06 in (150 cm) in length, more commonly 39.37 (100 cm).

It is native to the Burnett and Mary River systems of south-east Queensland, but has been introduced into other nearby rivers, including the Brisbane River. It prefers still or slow-flowing water with at least some aquatic vegetation on the banks, particularly deep pools.

Also known as the Australian lungfish, this creature normally uses its gills for respiration, but is also capable of taking in oxygen from the air when water quality is poor, or there are low dissolved oxygen levels, such as when water temperatures are high during summer. Unlike some other lungfish species Australian lungfish cannot survive the desiccation of their environment and require permanent water.

This species belongs to a very ancient group, Sarcopterygii (the fleshy-finned fish) which is over 400 million years old. Fossils of fish identical to N. forsteri have been dated at over 100 million years which makes this species one of the oldest extant vertebrate species.

Previously lungfish were considered to be the direct ancestors of amphibians, but now a common ancestor is recognized, although lungfishes did appear early in the history of vertebrates.

Spawning involves individual pairs of fish and complex behavior; however, unlike other lungfish species Australian lungfish do not exhibit parental care. Larvae resemble tadpoles, and are poor swimmers at first. Metamorphosis occurs early, when the fish are only about 0.79 in (2 cm) long. Juvenile adults grow very slowly, taking about two years to reach 4.72 in (12 cm). They have a long lifespan, however, sometimes living over fifty years.

Primarily carnivorous, the diet consists mainly of small fish, frogs and tadpoles and invertebrates, however they have on occasion been observed to consume some vegetable matter.

Proposed damming projects on both the Mary and Burnett rivers threaten the habitat of the remaining lungfish. The dams would change the flow of the rivers eliminating the slow shallow areas the fish need for spawning. Scientists worldwide have become involved in saving the habitat for these lungfish citing their evolutionary importance.

Queensland lungfish