The Chinese sturgeon is the largest fish in the Yangtze River and is known as the "King of Yangtze Fish." It can reach a length of 5 meters and weigh up to 600 kilograms. As a benthic carnivorous fish, it migrates upstream to spawn in summer and autumn, has a lifespan of up to 40 years, and is nicknamed the "Panda of the Water." It is a first-class nationally protected wild animal in China.

The Arapaima is a large freshwater fish from the South American Amazon River, reaching over 4 meters in length and weighing up to 230 kilograms. It breathes air using its swim bladder and must regularly surface. Primarily feeding on fish and occasionally preying on snakes and turtles, it is not only at the top of the Amazon River food chain but also considered a living fossil of the river.

The common sawfish inhabits tropical and subtropical coastal and freshwater areas, growing up to 7.5 meters long and weighing up to 600 kilograms. It feeds on fish, crustaceans, and mollusks, using its saw-like snout for hunting and defense. It is viviparous, with 1–13 pups per litter. Due to overfishing and habitat destruction, it is now classified as critically endangered.

The Marbled lungfish has an elongated, eel-like body and inhabits streams and lakes in West, Central, and Southern Africa. Belonging to the subclass of lungfishes that appeared about 400 million years ago, it is often called a "living fossil." Its swim bladder is richly supplied with blood vessels, allowing it to absorb oxygen and release carbon dioxide when oxygen levels are low.

The Albino iridescent shark catfish is freshwater fish from Southeast Asia, native to the Mekong and Chao Phraya rivers, reaching up to 1.3 meters in length and 44 kilograms in weight. An omnivorous species, it can breathe air using its swim bladder and prefers to live in schools in deep waters. Overfishing has made it endangered, and it is also an important species for aquaculture and ornamental purposes.