Harlequin Shrimp | Hymenocera picta Care & Info

We’ve already discussed a whole bunch of different types of invertebrates over here at FantaSEA. None of them are quite as spectacular-looking or wacky as the topic of this care guide, though: the harlequin shrimp.

Keep reading for everything you need to know about harlequin shrimp and their care!

Harlequin shrimp (Hymenocera picta) description

Where do we start?! There are many strange-looking marine shrimp out there but this one absolutely takes the cake. There are two varieties of harlequin shrimp, which are sometimes considered different species: Hymenocera picta and Hymenocera elegans.

Both harlequin shrimp varieties feature an unusual body shape that’s almost reminiscent of a praying mantis. They’ve got large, flat claws and flat eyes. Unlike other shrimp, which tend to have very long and thin antennae, theirs are flat and leaf-shaped.

Hymenocera picta, which is naturally found in the Pacific ocean, has a white body with purplish spots. Its cousin Hymenocera elegans from the Indian ocean features more reddish body spots. Both grow to a maximum size of around 2”.

Harlequin shrimp (Hymenocera picta) aquarium

If you’d like to keep a pair of harlequin shrimp in your own aquarium, keep in mind that these guys are pretty sensitive. High water quality is very important, which means they might not be the best choice for beginning aquarists.

Because harlequin shrimp don’t grow all that large, an aquarium of 10 gallons or up should work fine for them, although keep in mind that large aquariums are easier to keep stable.

Harlequin shrimp are not too picky when it comes to their surroundings. Just make sure the water flow is on the gentler side and provide plenty of hiding spots.

Harlequin shrimp (Hymenocera picta) compatibility

This species is naturally almost always found in pairs, so we recommend doing the same in the aquarium. Just keep in mind that harlequin shrimp are territorial, so if you want to keep more than one pair in the same tank, you’ll have to provide plenty of space.

As for tankmates, like other shrimp species, harlequins are aggressive towards other shrimp. In turn, they are vulnerable to attacks by larger fish species and might become withdrawn when combined with overly boisterous tankmates.

Many aquarists prefer keeping their harlequin shrimp in a single-species set-up or with very docile tankmates. Corals are fine, as harlequins have very specific dietary requirements that don’t include them.

Harlequin shrimp (Hymenocera picta) diet

Their highly specific diet is probably the most fascinating thing about this shrimp species. Harlequin shrimp only eat starfish and nothing else. Maybe they’ll have a nibble at the odd sea urchin, but that’s it. This is what makes them a bit more challenging to keep than many other shrimp: you’ll have to be able to provide a constant flow of starfish.

A few points about this strange diet of starfish:

• Harlequin shrimp only eat starfish legs. This means that you can keep a bunch of starfish in your refugium and snip off one of their legs for shrimp feeding time; the leg will regrow quite quickly.
• Asterina starfish, a small species that’s generally considered a pest, is one of the starfish on the menu. Yay! If any of your reef-keeping friends or your local aquarium shops are struggling with asterina, you can ask them to keep them for you after removal from the tank.
• You can buy starfish in bulk and freeze them.
• Be sure to remove uneaten bits after a few hours to prevent the aquarium water from spoiling.

Harlequin shrimp hunting behavior is fascinating. Larger starfish might be kept alive for days or weeks at a time while the shrimp feast on their legs.

Conclusion

A beautiful marine aquarium full of wacky and wonderful creatures like the harlequin shrimp is a joy to have in your home. If you’re dreaming of your own tank, don’t hesitate to contact us with your ideas. We design, set up and maintain aquariums for businesses and private clients!