Hovers above its bolt-hole with the first dorsal fin raised and flicking.
A dartfish to about 9 cm with a pale grey to cream body that darkens to deep purple over the rear half, a yellow head washed with magenta around the mouth and eye, and dorsal, anal and caudal fins edged in crimson and violet. The first dorsal fin is a separate tall pennant, raised and lowered continually as the fish hovers. The congener Nemateleotris magnifica, the fire goby, shares the shape and the raised pennant but is white in front and orange-red behind, without the purple and yellow.
Occupies a burrow or a gap under rubble and hovers just above it, singly or as a pair, feeding on zooplankton taken from the passing current. Recorded from about 20 m downwards and commonest below 25, which is deeper than the fire goby and puts it on the lower slope rather than the reef top. The flicking dorsal fin is the giveaway at distance. It bolts into the hole rather than swimming away, so a diver who has spooked one need only stay still: the fish reappears in under a minute, and repeated approaches from the same position are tolerated where a direct descent from above is not.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.
