The sailfin dottyback (Oxycercichthys veliferus), also known as the longtail dottyback, is a species of ray-finned fish from the family Pseudochromidae, the dottybacks from the Western Central Pacific where it is found on the Great Barrier Reef and other coral reefs in the Coral Sea,[1] where it is occurs inshore near rock and coral formations where there are sandy bottoms. This fish occasionally makes its way into the aquarium trade. It grows to a size of 12cm (05inches) in length. It is pale greyish to yellowish in colour and has bluish upperparts, a bluish dorsal fin which fades to yellow posteriorly and it has a dark blue spot at the anterior end of the dorsal fin.[1]