Lepidosiren

The South American lungfish, Lepidosiren paradoxa, is found across the Amazon, Rio Paraguay and lower Paraná basins. The only lungfish known from South America, it is an obligatory air breather and survives the dry season by aestivating in a mucous cocoon inside a burrow in the mud. It can reach 125 cm and live for well over 20 years, so whether it should be considered an aquarium subject at all is debatable.