Diet

• An opportunistic feeder that consumes detritus, organic material, small organisms, and carrion. It can scavenge material from the surrounding reef and sediment.

Range

• Tropical eastern Pacific, ranging from the Gulf of California and the Pacific coast of Mexico south through Central America to Colombia and Peru, with populations in the Galápagos Islands.

• In Mexico it occurs along much of the Pacific coast, including Guerrero.

• It occurs in the Zihuatanejo area.

Habitat

• Primarily associated with rocky shores, coral reefs, rocks, crevices, and spaces within living and dead coral.

• Found from the intertidal zone to at least 30 m and has been recorded to approximately 55 m.

• In the Mexican Pacific, specimens have been collected from coral reefs at depths of approximately 2–26 m and associated with coral, rocks, algae, and rhodoliths.

• Adults commonly occupy protected spaces within rocks and coral, while juveniles may occur directly on a variety of hard substrates.

Description

• One of the largest brittle stars found on Mexican Pacific coral reefs.

• Has a rounded disc covered with fine granules and five long, slender arms.

• Arms have stout, rounded to slightly flattened spines, with three and four spines alternating along the arm.

• Dorsal surface is typically dark brown to black, giving it its common name, Black Spiny Brittle Star.

• The disc may occasionally show a conspicuous white patch, while some individuals can be almost uniformly blackish-brown.

• Arms are readily broken when the animal is disturbed, allowing the brittle star to escape predators; lost arms can subsequently regenerate.