Invert of the Week - the Harlequin Shrimp

The Harlequin Shrimp –Hymenocera picta

With its oversized paddle claws and mottled coloration, the Harlequin Shrimp is one of the most out-of-this-world looking animals reef enthusiasts can put into their aquariums. As is the case with so many of the coolest looking reef animals, the special dietary requirements of the Harlequin Shrimp keep many people from owning them. The one and only thing an adult Harlequin Shrimp will eat are echinoderms, or for the non-nerd reefkeepers, seastars (starfish).

Common Name: Harlequin shrimp
Latin: Hymenocera picta, H. elegans
Origin: Hawaii, Red Sea, Indo-Pacific
Size: 1.5” / 3.8 cm
Diet: Only consumes echinoderms (seastars)
Difficulty: Moderate]
Temperament: Peaceful, with the exception of seastars (which it consumes readily)[/SIZE][/FONT]
Lifespan: A few years with good husbandry
Salinity: 1.023 – 1.026 specific gravity
Temperature: 74° F - 82° F
Lighting: N/A

The trick with keeping the Harlequin Shrimp alive is two-fold. Part one: feeding one is fairly straightforward. Provide seastars. Any seastar will work. I’ve let mine work through populations of Asterina sp. and then began manually feeding it whatever was available. Sand-sifting stars are by far my preference as they are larger, fairly inexpensive, and readily taken by my shrimp. It has taken Fromia sp. as well, but they tend to be more expensive and far less meaty. Chocolate chip stars (Protoreaster sp.) are many peoples’ food of choice. I, however, can’t risk one running loose in my reef tank, so I stick with “reef safe” seastars. Linkia sp. are another quality choice, but generally cost prohibitive.

Not on the list of food choices (generally) are brittle or serpent stars. These spindly arm speed demons are typically too fast for a Harlequin to catch (but never say never!). Although they are echinoderms, urchins are not generally eaten, but again, having tube feet may make them a target if the shrimp gets hungry enough.

The second part of keeping a Harlequin shrimp alive is the same thing that keeps all of the other animals in your tank alive. Water quality. Killing and eating a decent sized starfish can really degrade the water quality in a tank, so staying on top of this is equally as important as feeding the right food.

In my own tank, the Harlequin Shrimp is generally reclusive, only making its presence known at night when it’s not eating, or in the day when it’s really starting to get hungry — letting me know I’d better bring it home a starfish in the next couple days! All in all though, it is completely worth it to keep one of the most bizarre looking animals on a reef.


This article was submitted by James Culp, aka FlammySnake. Thanks!