A Scattered but Fascinating Range
Today's lungfish are found on three continents — Africa, South America, and Australia — in a distribution that reflects the ancient breakup of the supercontinent Gondwana. Their range is geographically fragmented, but each population is intimately tied to very specific freshwater environments.
African Lungfish: Seasonal Floodplains and Swamps
Africa is home to four species of lungfish, all in the genus Protopterus, and together they represent the most geographically widespread group:
- Protopterus annectens (West African lungfish) — Found across a broad band of West and Central Africa, including the Niger River basin, Senegal, and parts of Sudan. Inhabits shallow, slow-moving rivers, floodplains, and swamps.
- Protopterus aethiopicus (Marbled lungfish) — The largest living lungfish, reaching over 2 meters in length. Found in the Nile system, Lakes Victoria, Tanganyika, and Albert, and associated river systems in East Africa.
- Protopterus amphibius (Gilled lungfish) — The smallest Protopterus species. Found in coastal East Africa, including Somalia, Kenya, and Tanzania, typically in seasonal swamps and tidal areas.
- Protopterus dolloi (Slender lungfish) — Restricted primarily to the Congo River basin, where it inhabits swampy, heavily vegetated areas.
A defining feature of African lungfish habitat is seasonality. Many of the rivers, swamps, and floodplains they inhabit dry out completely during the dry season. African lungfish have evolved to cope with this by burrowing into the mud and aestivating — a behavior that no other fish on Earth can match in duration or extremity.
South American Lungfish: The Amazon and Beyond
South America has a single lungfish species, Lepidosiren paradoxa, known as the South American or Spotted lungfish. It is found primarily in:
- The Amazon River basin
- The Paraná River system
- Associated wetlands, floodplains, and oxbow lakes across Brazil, Bolivia, Paraguay, and Argentina
Lepidosiren prefers stagnant, densely vegetated, oxygen-poor waters — exactly the conditions where its air-breathing lung provides a decisive advantage over gill-breathing fish. It is particularly associated with the Pantanal, the world's largest tropical wetland, where seasonal flooding and drying create ideal conditions for a facultative air-breather.
Australian Lungfish: A Single River System
The Australian lungfish, Neoceratodus forsteri, is the most geographically restricted of all living lungfish. It is native to just two river systems in southeast Queensland:
- The Burnett River
- The Mary River
Unlike its African and South American relatives, Neoceratodus prefers permanent, deep, clear-water rivers with abundant aquatic vegetation and slow currents. It does not aestivate, and it requires reliable year-round water flow. This restricted natural range makes the Australian lungfish particularly vulnerable to habitat changes.
Populations have also been introduced to several other Queensland rivers — including the Brisbane, Albert, and Coomera rivers — through human translocations in the late 19th and early 20th centuries.
Habitat Summary at a Glance
| Species Group | Region | Preferred Habitat | Seasonal Tolerance |
|---|---|---|---|
| Protopterus (4 spp.) | Sub-Saharan Africa | Swamps, floodplains, slow rivers | Survives complete drying via aestivation |
| Lepidosiren paradoxa | South America | Stagnant wetlands, oxbow lakes | Tolerates seasonal drying; aestivates |
| Neoceratodus forsteri | SE Queensland, Australia | Deep, clear permanent rivers | Requires permanent water; does not aestivate |
Why Distribution Matters for Conservation
The restricted and fragmented distribution of lungfish makes them especially sensitive to habitat change. Water extraction, dam construction, pollution, and climate-driven changes to rainfall patterns all directly threaten the specific environments these animals depend on. Understanding exactly where they live — and what habitat conditions they require — is a foundational step in any meaningful conservation effort.