The Scissortail Goby (Ptereleotris evides) is greenish-blue in the front, gradually changing to almost black towards the rear. The forked tail is long like the blades on a pair of scissors, especially in adults.
Dartfish are long, slender fish from the Ptereleotridae family that are often found hovering higher in the water column than most gobies that live in or on surfaces and rockwork. This family includes the popular Firefish Gobies (genus Nemateleotris) and other similar and popular aquarium fish. Dartfish are ideal for reef aquariums. They do best on a diet of live foods like plankton and small crustaceans but will also eat small meaty frozen foods. Diet can consist of small meaty frozen foods or small flake and pellet foods.
Dartfish need plenty of rockwork to hide in and feel comfortable. The name "Dartfish" comes from their habit of "darting" quickly back into the rockwork whenever threatened or frightened. Dartfish are often skittish and easily frightened; a tight-fitting lid is recommended to keep the fish from jumping out of the aquarium. They are peaceful toward other fish but may become territorial if they are crowded in small aquariums (particularly with members of their own species). Though it may take them some time to become comfortable and active, they often act as "dither fish" and their activity can encourage other shy fish to come out into the open more often.