1. Longtu is a kind of catfish, also called catfish or catfish dragon, which is mainly distributed in rivers and lakes in Southeast Asia. The earth dragon has a long and flat body, a wide head, a big mouth and sharp teeth, and is suitable for preying on other fish and aquatic insects.
2. Eel is a kind of fish of the order Anguilla, also known as eel or river eel, which is mainly distributed in rivers and oceans all over the world. Eels are slender and snake-shaped, with small head, small mouth and no sharp teeth, which are suitable for preying on small aquatic animals.
Earth dragon is an eel that looks like a snake. There are some differences between them in definition and appearance.