Anago (穴子, or アナゴ, Anago?) is the Japanese word for salt-water eels, which are a seafood dish in Japan. Anago are often simmered (sushi) or deep-fried (tempura), compared to unagi (freshwater eels) which are usually barbecued with a sauce (kabayaki). Anago is also slightly less rich and oily than unagi. - Wikipedia
Many had tried Unagi, but have you tried Anago before? Anago is a sea eel. Read more about it here.