Scissortail Dartfish

About

The scissortail dartfish (Ptereleotris evides) is a slender, elegant dartfish from the Indo-Pacific, ranging widely from the Red Sea and East Africa out to the Line and Society Islands, with populations extending north toward Japan and south to New South Wales and Lord Howe Island. In the wild it turns up on outer reef slopes, lagoons, and bays, where adults are typically spotted in bonded pairs hovering a foot or two above the substrate while picking zooplankton from the water column. That hovering behavior is one of its most recognizable traits. It looks almost suspended in midwater, working the current for tiny prey. Unlike many of its relatives, this species tends to swim away from threats rather than diving headfirst into a burrow, which makes it somewhat more visible and entertaining to watch in a display tank. Juveniles form loose groups, but adults are notably monogamous, so if you can source a mated pair, you'll get a real glimpse of natural behavior. The body is pale blue-grey fading to a yellowish tail, with a deeply forked caudal fin that gives it the "scissortail" nickname. It's a reasonable choice for a reef setup with plenty of open swimming space and a tight-fitting lid.