Two-spined sea star

Astropecten duplicatus

Family Astropectinidae - starfishes

Body star-shaped with 5 arms that taper to a point; color reddish brown or gray; sides of arms with marginal plates (upper and lower), upper plates protrude slightly above middle of arms, lower plates protrude slightly beyond upper plates; the area in between the upper plates at the base of the arms is about twice the width of the upper plates; surface of plates granular; the 2 upper marginal plates between the arms (and sometimes surrounding plates) bear a tubercle spine on the inner edge of the upper surface, many times the spines are worn down; lower plates and underside plates with many small spinules (very fine spines) that are somewhat flattened and blunt at the tips; the mouth plates on the underside covered with small blunt spines; small round plate (madreporite) on upper surface between arms and center of disc with squiggly folds.
Similar Species
The marginal plates helps distinguish this family of sea stars. The spines on the inter-arm plates (when present) distinguish this species from others of its genus.
Gulf, sandy or soft sediments.
Maximum Size
20 cm (8 in)
Other Common Names
Previous Scientific Names