The Nebulous wrasse (Halichoeres nebulosus) is also known as the Clouded rainbow fish, Clouded wrasse and the Picture wrasse. They are small colourful fast moving wrasses that are common on the reefs and surrounding areas in Tanzania, particularly on the shallower reefs.
The juvenile Nebulous wrasse pictured above has a silver colored lower body with a square red marking on the lower mid body. The upper body has mottled maroon and black colouration and there are orange lines on the lower face. The eye has a light blue ring around it which seems to stay as the fish ages. There is considerable variation in the patterns between specimens.
As the fish ages so the body develops more green on it and the orange facial lines become more apparent. Some specimens lose the maroon bar on the lower belly and this may be as a result of sexual differentiation as most of the larger specimens do not seem to have it. More research is necessary to see if this is correct. All in all they are attractive looking fish whose colours provide good camouflage on the reef. They grow up to 12 cm in length.
NEBULOUS WRASSE IN THE WILD
The Nebulous Wrasse is fairly common in Tanzanian waters, both on reefs themselves and on surrounding rubble. They are more common on shallower protected reefs with good algal growth but they are seen on deeper reefs down to approximately 15 meters. When a diver approaches they will often hide in soft corals.
The Nebulous Wrasse is found across the Indian Ocean and the West Pacific. They mainly prefer the shallower reefs with more algal growth and are more common in these areas. They are seen down to 15 meters but are not as common at this depth.
The Nebulous Wrasse feed on benthic invertebrates and fish eggs.
As with all the Halichoeres species, they are protogynous hermaphrodites. This means they are all born female and at some point in their lives have the ability to change to males. Males are less common than females and they have a haremic structure. Breeding takes place in spring in Tanzania and by autumn the new juveniles are approximately 4 cm long.
Nebulous Wrasse are kept in aquariums but probably not that commonly. They are active fish and a long tank with hiding spots and sand would suit them best. They will not be reef safe and could pick on shrimp and corals. A sister species Halichoeres melanarus has been bred in captivity. They are hardy fish and are able to survive in the tidal shallows with a large temperature differential.
NEBULOUS WRASSE CLASSIFICATION