The colour is variable depending on its environment, being dark when swimming over beds of mussels and cream or tan when above a sandy seabed.

Its range extends from Malaysia and southern Japan, through Indonesia and Samoa to western, northern and eastern Australia.

It is a demersal species and is found in estuaries and on algae-clad rocky coasts as well as over muddy and silty seabeds, on seagrass meadows and on reefs, both on and offshore, to depths of about 50 m (164 ft).

Besides feeding on algae and seagrass, it preys on small invertebrates such as amphipods, caridean shrimps, copepods, tanaids, bryozoans, hydroids, polychaete worms and tunicates.

[4] About 40% of the diet is animal matter, and this species is very dependent on encrusting organisms and the epiphytic algae and invertebrates present in a seagrass meadow.