Aspect: Flat blades, usually green or green with blue or brown tones, that fork off in Y patterns - hence their English designation. Can spread over relatively wide surfaces. Population: Widespread. Notable feature: Belongs to the Brown Algae category in spite of its usually predominent green colour (algae are subdivided into four colours: Brown, Green, Red and Blue-Green. Environment: Can grow over many substrates, and as exemplified by some of the photographs herewith, can even develop over leaf corals. Behaviour: -
