The black tongue stick mainly feeds on zooplankton (such as crab larvae, arrow worms and planktonic tunicates, etc.), and sometimes also eats red thread algae. The black tongue hangs mostly in waters between 6-150 meters deep in clear lagoons and outer reef slopes.

Black tongue hornsAdults have bluish-grey back, pale yellow abdomen, dark brown gill membranes, more than 25cmBlack tongue hanging, black tongue, hence the name black tongue hanging. Generally, there are no markings on the side of the body, and the maleblack tongue hangingmaybe on the head The upper part has light blue spots, and the front part of the body has some light blue transverse bands or spots. The caudal fin is light blue or slightly darker, and the caudal margin is yellow-green.