Harlequin Shrimp

Found in pairs on algae and sponges, over coral and rocky reefs, rarely moves far from the same spot.
They feed on sea stars by flipping over their prey and eating a leg at a time. Very occasionally they flip over sea urchins and eat their tubed feet.

Hymenocera picta, commonly known as Harlequin Shrimp, is a species of saltwater shrimp found at coral reefs in the tropical Indian and Pacific oceans. It is usually considered the only species in the genus Hymenocera, but some split it into two species: H. picta from the central and east Pacific where the spots are deep pinkish-purple with a yellow edge, and H. elegans from the Indian Ocean and west Pacific where the spots are more brownish and have a blue edge. They reach about 5cm in length, live in pairs and feed exclusively on starfish, including the crown-of-thorns sea star.