Forktail fang blenny

Meiacanthus atrodorsalis, the forktail fang blenny, is a combtooth blenny in the family Blenniidae, native to reefs of the western Pacific. It has a slender pale body shading from lavender-blue at the head to yellow toward the deeply forked tail, with a dark stripe through the eye. It is a hardy, generally peaceful fish that hovers in open water rather than perching. It possesses venomous fangs used purely in defense, which deters predators and lets it coexist confidently with many tankmates; it may squabble with other fang blennies. It suits peaceful reef aquariums with live rock offering crevices for retreat and sleeping. It is reef-safe and an omnivore, feeding on mysis, brine shrimp, and prepared foods, plus grazing on films. A secure lid helps prevent jumping. Its coloration is mimicked by other reef fish, a classic example of protective mimicry.