Nemateleotris decora, the elegant firefish or purple firefish, is a species of dartfish native to tropical waters in the Indo-West Pacific, from Mauritius to Samoa, north to Ryukyu Islands, and south to New Caledonia, from depths ranging between 25 to 70 m (82 to 230 ft). It is found over hard, open bottoms of reefs, sandy patches and rubble, as well as deeper coastal outer reef drop-offs where there are strong currents. It reaches a maximum length of 9 cm (3 in). This species is often found in pairs and is monogamous. They feed on zooplankton, especially the larvae of copepods and crustaceans. They will dart into holes when alarmed.