Although a predominantly tropical species, occurring in tropical marine waters worldwide, the unicorn leatherjacket is known from the central coast of NSW to northern Australia to as far south as Geographe Bay, WA.
Attaining a large size of upto 75 centimetres, the unicorn leatherjacket has a highly compressed pale bluish grey body covered in brown spots. They have a slender dorsal spine atop their head. Adults are considered pelagic as they form large schools in the open ocean, often swimming below large floating Sargassum mats. Occasionally they can be found in shallow water in small groups, but generally only enter shallow coastal bays and estuaries to nest. Juveniles float with the oceans currents and have been associated with large swimming jellies which sometimes bring them close to shore.
Other common names include: Unicorn Filefish
Occurrence at the Busselton Jetty:
The unicorn leatherjacket is a transient visitor to the waters surrounding the underwater observatory and is observed on a rare basis as they pass through the area.