Reef squid are small (for a squid), only growing to around eight inches in length. Their body is torpedo shaped, with a hood-like upper body called a mantle, and eight short arms near their mouth. They have two longer tentacles that they use to snatch animals to eat.
The squid’s normal color is a green to brown color, darker above and lighter below, but they are able to adjust and control their pigment to display a wide range of colors and patterns. They are known to communicate by flashing different colors and patterns at other squid, signaling warnings and desire to mate. Their coloration will grow paler when fleeing predators. They will also turn a red or deep brown color in order to camouflage with their reef surroundings.