Blue Zoo: Harlequin Shrimp
Featuring one amazing marine animal per week.
The harlequin shrimp (Hymenocera picta) is a small but vividly colored resident of the coral reefs of the Indo-Pacific. The species only grows to about 5cm (2 inches) long. Thanks to their brightly patterned shells, they are sometimes also called painted shrimp or clown shrimp. They can also be recognized because of their large flattened claws, called chelipeds.
Photo by Steve Childs via Wikimedia Commons, Creative Commons License.
Some scientists suggest that the harlequin shrimp is actually two different species that are very similar, named Hymenocera picta and Hymenocera elegans but this difference isn't entirely agreed upon.
These distinctive and diminutive reef residents tend to live alone or in pairs. They may stay in monogamous male-female couples over relatively long periods of time. The mated pairs share territory and prey – and they have been noted to be territorial against other shrimp.
Photo by Steve Childs via flickr, Creative Commons License.
Harlequin shrimp specialize in hunting sea stars. They prefer smaller ones but are capable of taking down the formidable crown of thorns (Acanthaster) sea star. The harlequin shrimp flip the prey sea star over onto its back, rendering it defenseless, and then eat the tube feet and other soft tissues.
Photo by Chad Ordelheide via Wikimedia Commons, Creative Commons License.