It has a relatively small, oblique mouth with the upper jaw just reaching, or falling short of, the front of the eye.

The colour pattern is light greyish to brown dorsally, silvery to white ventrally with 4–5 broad dark vertical bands on the flanks which are more obvious immediately above the centre of the flanks.

[2] The sea trumpeter is commonly found in seagrass beds in shallow water.

The juveniles frequently hide amongst seaweed, seagrass or floating mats of macrophytes.

[3] The sea trumpeter was first formally described in 1899 as Therapon humeralis by James Douglas Ogilby with the type locality given as Pelsaert Island in the Houtman Albrohos.