Macquaria ambigua, commonly known as the Murray cod, is a large freshwater fish native to the rivers and lakes of eastern Australia. It is characterized by its robust body, large mouth, and distinctive greenish or brownish coloration with lighter mottling. This species can grow up to 1.8 meters in length and weigh over 100 kilograms, making it one of the largest freshwater fish in Australia. The Murray cod is an important species for both ecological balance and recreational fishing. It primarily feeds on smaller fish, crustaceans, and aquatic invertebrates. Due to habitat loss and overfishing, Macquaria ambigua populations have declined, leading to conservation efforts aimed at protecting this iconic species and its natural habitat.