Harlequin shrimps spend their lives in monogamous pairs, working together to trap their favourite food: starfish. They find the starfish by smelling with their antennae, then the two of them turn the much bigger animal over and feast on its tube feet. Sometimes they will take the starfish into a dark recess of their reef territory, where they will eat it alive over several days.
Exquisitely patterned, Harlequin shrimp grow to 5 cm. Two species claim the name of Harlequin Shrimp: Hymenocera elegans and Hymenocera picta. They look similar, but the former lives in the shallows of the Red Sea to Indonesia; you find the latter more easterly in the Pacific.
Harlequin shrimp are a favourite with underwater photographers. Once you spot one it is easy to photograph, but they are uncommon and so take some spotting in the first place.
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