Lungfishes
Lungfishes are a group of freshwater fish that belong to the subclass Dipnoi. They are characterized by their ability to breathe air using a specialized organ called a lung, in addition to gills. Lungfishes possess elongated bodies and can grow to be quite large, with some species reaching lengths of over six feet. They are known for their unique evolutionary history, having existed relatively unchanged for millions of years. Lungfishes are primarily found in Africa, South America, and Australia, where they inhabit shallow, stagnant waters such as swamps and marshes. These ancient fish are considered living fossils and are of great interest to scientists studying the evolution of vertebrates.