News / Species Spotlight / Harlequin Shrimp (Hymenocera picta) (04/06/17)

Harlequin Shrimp (Hymenocera picta)

Species Spotlight Harlequin Shrimp (Hymenocera picta)
Harlequin Shrimp, also called Clown Shrimp due to their somewhat comical appearance, are one of the most striking and desirable species of shrimp commonly available to marine aquarists. There are two color variants of Harlequin Shrimp found in different regions of the ocean. The Indo-Pacific variant features a body that is mostly white with blue to purple splotches throughout and the Hawaiian variant features the same white body, but has bright magenta splotches and some yellow and orange coloration as well. Both variants have the same, humped body, two irregular, white antennae with large, flat, main claws featuring surprisingly small pincers and striped legs. Determining the sex of a Harlequin Shrimp is very easy as males have no coloration under their tails, while females have thick stripes.

Harlequin Shrimp are best kept singly or in pairs and are peaceful towards other aquarium inhabitants. They are somewhat cryptic shrimp and may prefer the shadows of the rockwork in a high-energy reef aquarium, but most individuals will get used to their surroundings and begin to explore. Like all shrimp, Harlequins are vulnerable to larger fish that may try to eat them such as some wrasses, pufferfish, and other predators and it is therefore important to consider their tank-mates before adding one to your reef.

Perhaps the most important thing to consider before purchasing Harlequin Shrimp is their highly specialized diet. Harlequin Shrimp are obligate predators, meaning that they are restricted to eating only one type of prey. They only eat sea stars, specifically the tube-feet of the stars. This is the main reason that many aquarists covet these shrimp for their ability to eradicate Asterina sea stars infestations. It is important to remember that once an infestation is eliminated, however, that other stars must be supplied weekly to keep the shrimp well fed. The food of choice for most aquarists is the Chocolate Chip Stars due to its size, lower cost, and availability. Although the starfish might be much larger than the Harlequin Shrimp, the shrimp can maneuver the sea stars with ease thanks to their incredible strength and specialized appendages used to keep the sea stars from gripping the substrate.

Harlequin Shrimp are one of the most fascinating species of shrimp and can make a great addition to almost any reef aquarium. With recent advancements in captive breeding, we are hoping captive bred Harlequin Shrimp will become widely available. If you are interested in adding an individual or pair to your aquarium, be prepared to assume its specialized food requirements, but to also be rewarded by the beauty and character of this amazing shrimp.