Oreaster reticulatus

The red cushion sea star, also called the West Indian sea star, is a marine invertebrate belonging to the family Oreasteridae. It is the largest sea star in its range, reaching up to about 50 centimeters across, and lives in shallow waters of the western Atlantic Ocean and the Caribbean Sea.

This starfish typically has five thick, broad arms extending from a wide, cushioned central disc, though some individuals have four, six, or seven arms. Its hard upper surface is covered with blunt spines. Adults range in color from red, orange, and yellow to brown, while juveniles are greenish-brown with mottled patterns.

The species is found across the Western Central Atlantic, including the Bahamas, Cape Frio, Cape Hatteras, the Caribbean Sea, Florida, the Gulf of Mexico, the Guyanas, and Yucatán. Adults usually inhabit sandy bottoms and coral rubble at depths up to 37 meters, whereas juveniles live in seagrass meadows, where their coloring provides camouflage. During winter, they migrate to offshore areas with little water movement to avoid turbulence.

An omnivore, the red cushion star feeds on seabed sediment, epiphytic algae, sponges, and small invertebrates. It rakes sediment into piles, then everts its cardiac stomach to engulf the mass. It prefers edible sponges over other prey, and where the starfish are abundant, those sponge species tend to disappear.

The sexes are separate. In subtropical regions, breeding occurs in summer; in more tropical areas, it happens year-round. Large groups gather at breeding sites, sometimes reaching densities of fourteen individuals per square meter, which increases the chance of fertilization when gametes are released into the water. The larvae drift as part of the zooplankton, and after several developmental stages, they settle on the seabed—often among seagrass—and metamorphose into juveniles.

Harvesting this species is illegal in some places, including Florida waters.