The Fire Goby, Fire Fish, Fire Dartfish, or Red Fire Goby is a marine dartfish. This fish is most commonly found near the substrate of the upper reef in tropical marine waters. These waters include the Indo-Pacific, Central Pacific, east African waters, Ryukyu Islands, Japan, New Caledonia, and Pitcairn Islands. They swim as deep below the surface as 70 meters, and usually hover directly above the ocean floor, facing the current to catch their prey. They eat mostly copepods, zooplankton, and crustacean larvae. They usually have a bright yellow head, merging into a white body, gradually shading into a red-orange tail. Their dorsal fins are very long, and the fish flicks it back and forth. This is used as a signal to conspecifics. As a full grown adult, it reaches a maximum length of 9 centimeters (3 in). Adults occupy sandy burrows alone or in pairs, while the juveniles live in small groups. These fish are monogamous. They will retreat to burrows if threatened.