A small boxfish in a rigid shell, the males patterned in blue and orange lines. Slow, easy to approach and one of the most photographed fish in southern Australia.
To 15 cm. Males and females look like different fish and both need describing. Males have yellow sides carrying a regular arrangement of blue-centred black spots, and a distinct bump in front of the eye. Females have red, white and black stripes running along the sides, a deeper body and no bump. Both sexes have a small rigid bony box with a sharp ridge along the back, narrow dorsal spines, and the hovering, sculling swimming style of the family.
Shaw’s cowfish is the other cowfish of southern Australia. Males are separated by the narrower dorsal spines and the spot pattern. Females of the two are genuinely hard to tell apart, and there is no point pretending otherwise.
This is a temperate fish of southern Australia — southern Western Australia through South Australia and Victoria to Tasmania and southern New South Wales. It is not a tropical species and it does not occur on the Great Barrier Reef. It lives on temperate reef, seagrass, kelp, sand and sponge gardens between 5 and 60 m and usually above about 20. It is slow, solitary and feeds on small bottom-living invertebrates. Like other boxfish it releases a skin toxin when stressed, which matters only to fish in a confined space.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.