In terms of appearance of the animals themselves, the eels might seem quite similar at first glance, but there are subtle differences
Unagi, or freshwater eel, have an elongated shape, which makes it easy for them to navigate through water. Anago, or sea eels, have a more flexible body to adapt to marine environments.
Unagi also have rougher skin textures and a darker colouration, typically showcasing shades of green or brown. In contrast, the skin of anago is usually smoother, displaying a lighter colour with hues of beige or light brown.