This is a black and white guppy, which likes to peck at soft corals, sponges and other invertebrates.

The black and white guppy is a relatively common tropical marine fish. The curved back is the symbol of the guanabo, and is also the origin of its Chinese name. Countless pairs of swordfish swimming in the coral reef, black, white and yellow body color contrast bright, like a butterfly in the flowers, so its English name directly translated is "white butterfly fish".