The spiny butterfly ray (Gymnura altavela) gets its name from its wide, characteristically wing-like pectoral fins, and its short, sharp tail, which has serrated spines on both sides, used to stun prey.

The upperparts of the spiny butterfly ray are usually brown to grey, sometimes with reddish-brown shading at the margins of the ‘wings’. Small dark or light spots and blotches may produce a marbling effect across the back. The colouration of the spiny butterfly ray, along with its wide, flat, disc-shaped body enable it to effectively camouflage itself in sand beds. The underside is generally white, brown or rosy-coloured. The spiny butterfly ray has a blunt snout, and the jaws contain many rows of teeth.

The juvenile spiny butterfly ray has paler skin, which darkens to brown as it mature.