HARLEQUIN SHRIMP (Hymenocera picta)
The Harlequin Shrimp is one example of a non-toxic crustacean bearing vivid colours, which serve as 'false advertising' by being enough to scare predators away. The ones found in the Indian Ocean and West Pacific have white bodies that are covered in large purple spots with a blue edge. They are a monogamous species, which means when they find a mate they stay together for life in pairs that are often territorial. The pairs often take shelter in the base of branching coral heads, in crevices or under rocks below the inter-tidal zone on coral reefs, and they can be found in the same area of the reef for months and even for years. They are a rare animal because of the changing coral reefs and due to their high sensitivity to water temperature, salinity and water chemistry.
The Harlequin Shrimp has 5 legs on each side, of which the first pair are modified large,
flattened claws known as chelipeds. Their eyes sit on stalks and they have a first pair of
sensory antenna on the head that they use to sense the smell of nearby prey. They can grow
up to 5 cm in length, females growing slightly larger than males. These shrimp feed mainly
on echinoderms, particularly starfish, which they are able to turn over to disable it prior to
starting their meal at the end of one arm and eating up to the central disk of the still alive
starfish. They can feed on the same starfish for days, keeping it immobilized, while slowly
eating away its insides. They usually hide during the day and prefer to feed at night. Their
reproduction is sexual with 100 to 5,000 eggs being laid per season which the female tends
and cleans until they hatch.
PLEASE NOTE THAT AN ENCOUNTER WITH A HARLEQUIN SHRIMP CAN NEVER BE GUARANTEED ON A PARTICULAR DIVE!! This is what makes the wild so special; every day is just unique!