Introduction to the Australian Lungfish
The Australian Lungfish, also known scientifically as Neoceratodus forsteri, is an interesting and underrated species of fish. Found natively only in the waterways of eastern Australia, this species is incredibly unique in both its physicality and behavior, making it an incredibly fascinating aquatic creature.
The Australian Lungfish is the only species within its genus, Neoceratodus, and the sole living representative of an ancient family of fish known as the Ceratodontidae. This highly resilient species has been studied extensively and evidence suggests that it has remained practically unchanged for approximately 150 million years, likely due to its lack of natural predators. Moreover, the Australian Lungfish is considered to be the closest living relative to the earliest tetrapods, the first of the four-limbed vertebrates.
Fascinating Features of the Australian Lungfish
The Australian Lungfish has a range of extraordinary features that have allowed it to persist for so long. These features include its remarkable lungs, fins, and lateral line system as well as its extraordinary behavior.
The Australian Lungfish is best known for possessing both true lungs and an operculum. This means that the Lungfish can, quite remarkably, breathe air as well as water. The Lungfish’s pulmonic lungs consist of a main bronchus and four secondary bronchi, each connected to a chamber known as the “pulmonary cavity”. During respiration, the Lungfish gulps atmospheric air, forcing it into this pulmonary cavity, which is filled with vessels. There, the air is modified, oxygen is scavenged and carbon dioxide is expelled, allowing the Lungfish to survive in low-oxygen conditions. The Lungfish is therefore capable of surviving in conditions where no other fish can, such as during droughts.
The Australian Lungfish is also equipped with 7-9 dorsal finlets, which run all the way to the caudal, or tail fin. These finlets are highly sensitive and are presumably used to navigate aquatic environments and detect changing water pressure. The Lungfish also has a well-developed lateral line system which, like the finlets, assist in navigation.
The Fascinating Social Life of the Australian Lungfish
Another interesting aspect of the Australian Lungfish’s behavior is its social life. Lungfish are highly social and reside in colonies. A Lungfish colony typically consists of a single male Lungfish who will court multiple female Lungfish in close proximity. This process involves the male Lungfish displaying a range of body language including colorful posturing and excellent feats of strength.
During the mating season, which takes place in and around December and January, the female Lungfish will lay eggs which are then fertilized by the male Lungfish. These eggs are then left to develop and hatch on the river bed, taking anywhere from weeks to months for the process to be complete. Once the eggs have hatched, the male Lungfish will remain in vigil until the young have matured enough to look after themselves.
The Conservation Status of the Australian Lungfish
The Australian Lungfish is listed as being of ‘least concern’ on the IUCN Red List and is not currently under any known conservation threat. This is incredibly fortunate considering the species is found only in its native habitat, the rivers of eastern Australia. Nevertheless, the species is still subjected to occasional threats due to water pollution and runoff. As such, the Australian Lungfish remains on IUCN Red List, as monitoring and research is still needed to ensure its continued survival.
The Australian Lungfish is also listed as a species of national interest on the Environmental Protection and Biodiversity Conservation Act, making it illegal to capture or trade in the species.
Conclusion
To conclude, the Australian Lungfish is a remarkable species of fish, able to survive for over 150 million years due to its extraordinary features and behavior. What’s more, the Australian Lungfish is believed to be the closest living relative to the earliest tetrapods, making it an important species in the study of ancient life forms. Moreover, research suggests that the Australian Lungfish is not currently threatened with extinction, which makes it a species worth conserving. Ultimately, the Australian Lungfish is a fascinating species of fish, one which offers a fascinating insight into ancient aquatic life.