The multicolored knobbed starfish is a tropical sea star with a thick, fleshy body. It has five short, robust arms extending from a very prominent central disk. Its upper surface is covered with numerous tubercles, small rounded or sometimes pointed protuberances that give it a particularly knobby appearance. A prominent row of these tubercles generally runs along the center of each arm, while others are distributed across the disk and along the margins.

Its coloration is variable, with a body generally ranging from light brown to beige, sometimes grayish, contrasting with tubercles that can be much more colorful, particularly in shades of red, orange, or brown. It can reach about 12 inches in diameter.

The multicolored knobbed starfish is found in the tropical waters of the western Indian Ocean, particularly along the eastern coast of Africa, including Kenya, Tanzania, Mozambique, and as far south as South Africa. It is also found in the waters of the Persian Gulf, including Qatar.

The multicolored knobbed starfish lives in shallow tropical waters, generally from a few feet to about 50 feet deep. It is commonly found on sandy bottoms or coral rubble near reefs, as well as in sheltered areas and seagrass beds.

The multicolored knobbed starfish moves slowly across the seafloor in search of food.

The multicolored knobbed starfish has a fairly varied diet. It feeds on organic debris and small organisms found on the surface of the seafloor, as well as microorganisms that grow on algae, seagrass, and the substrate.

It can also consume organisms attached to or living on the seafloor, including invertebrates. In the Persian Gulf, in Qatar, it has notably been observed feeding on pearl oysters (Pinctada radiata), which it can open before digesting their tissues.

Like other sea stars, it can evert its stomach outside its body to digest its food before absorbing it.

As in other sea stars, the multicolored knobbed starfish reproduces sexually. After the gametes are released, the fertilized eggs develop into larvae that live in the plankton before undergoing metamorphosis and settling on the seafloor.