The Harlequin Shrimp have a white body with blue spots, and the males are slightly smaller than the female. It differs from its close cousin, the Hawaiian H. picta
which has purple and red spots. It has large claws which are mostly for show as it does not hunt with them.
The Harlequin Shrimp is best kept as mated pairs in an aquarium with moderate light. They can however be kept successfully without a mate. They cannot tolerate copper or high nitrates, and iodine levels must be correct and maintained to ensure proper molting.
Harlequin Shrimp eat only echinoderms, primarily starfish, and a few urchin species. It will eat starfish (Asternia, Linckia, Fromia sp.) by starting at the tip of the arm and working its way to the central disc. The starfish may shed the arm, but is often mortally wounded.
As its primary source of food, you will need to supply the Harlequin Shrimp with starfish. The adults may also eat sea urchins.