Queensland lungfish
Australian lungfish ( Neoceratodus forsteri )
Called the Australian lungfish ( Neoceratodus forsteri ), also Djelleh, Barramunda, Burnett Salmon or Queensland lungfish, is the only Australian representative of only a few species overall order of the lungfish. He is considered the most primitive kind of order. The lungfish are well known with a great diversity of species in the fossil record dating from before 400 to 230 million years ago. Therefore, the three kinds of the extant species are also referred to as a living fossil. The Australian lungfish was only discovered in 1870.
Occurrence
He originally came only in the Burnett and Mary River systems flow front in south-eastern Queensland, Australia. However, he was successful later settled in several adjacent rivers, such as in Brisbane, Albert, Coomera and Stanley River and Enoggera Reservoir.
The Djelleh lives, as opposed to other styles, not completely drying up, slow flowing and standing waters. Here he helps his lungs, which formed during the partial evaporation of the water oxygen conditions to survive. With increased activity or in times of drought, when the oxygen supply is insufficient about the gills, he gets twice per hour to the surface to breathe. The sound when breathing out is reminiscent of a small bellows.
Description
The upper side brown olive, the under side bright fish with the long - stocky body kg is usually up to 90 cm, and occasionally 1.75 m long and up to 10 hard. In the flattened head sitting little eyes. He has muscular chest and pelvic fins arms with which it can move slowly across the mud on the river bottom. The approach of the dorsal fin is in the middle of the back, it is fringe- fused with the caudal and anal fins. He has, in contrast to the South American and African lungfish very large, bony scales.
Like all of the Australian lungfish can lungfish breathe with a lung except with gills. Unlike the types of Lepidosireniformes which form a bipartite lungs, he developed only one. As with the other species of lungfish, also this is divided with an elaborate system of partitions into small breathable chambers. Except for the single lung respiration is used in this type but in addition to the lift generation. Accordingly, the lungs of the Australian lungfish has also not such a great efficiency in oxygen uptake, and as an optional air-breathers he inhabits habitats with a much lower need for air breathing as the obligate air-breathers of the African and South American lungfish. For this type has taken a small step towards a controllable buoyancy organ.
Virtually identical -looking fossils of a lung fish compared to extant Neoceratodus have been unearthed in northern New South Wales. This species has survived practically unchanged for more than 100 million years, making it one of the oldest extant vertebrates.
Nutrition
The fish is mainly nocturnal and feeds on frogs, tadpoles, fish, invertebrates and aquatic plants. It can with the help of his tooth plates in both jaws and hard clams and snails crack.
Propagation
Spawning season is in running waters from August to December before the summer rains, when water temperatures rise above 20 ° C. After extensive courtship behavior is spawned in pairs between aquatic plants. The spawn consists of gelatinous lumps with large eggs, resembling frog spawn. The hatching after 3 to 4 weeks juveniles remember tadpoles and only breathe through gills. The young fish are often side on the ground. Under optimal conditions, they can reach 25 cm in length in the first half a year, but usually they are much smaller.
Use
The fish was a popular food fish, but is now a nature reserve.
Threat
Although the type due to the present distribution area does not appear in acute danger, it is strictly protected.
By decree of 6 May 2006, the government of the Australian state of Queensland has decided to build a dam on the Mary River. This will destroy important spawning grounds of the species, and are potentially at risk, the remaining population.