Harlequin Shrimp

Harlequin Shrimp: The Starfish Specialist

The Harlequin Shrimp (Hymenocera picta) is one of the most uniquely beautiful and captivating invertebrates in the marine aquarium hobby. It is instantly recognizable by its ornamental, white to cream-colored body adorned with large, vibrant spots that range from red and pink to purple or blue. Its oversized, flattened claws resemble flower petals, which contribute to its flamboyant appearance. This Indo-Pacific species is a highly specialized animal and should only be kept by aquarists prepared to meet its single, critical dietary requirement.

The Harlequin Shrimp reaches a modest maximum size of only about 1.5 to 2 inches (4-5 cm). Its diminutive size and peaceful temperament make it suitable for smaller, peaceful tanks, with a minimum size of 10 gallons recommended, provided water quality is rigorously maintained.

The Harlequin Shrimp is renowned for its highly specialized hunting behavior. Often found in a devoted monogamous pair, they will work together to hunt, flip, and consume starfish much larger than themselves, making them the ultimate natural predator for nuisance Asterina starfish.

Diet & Compatibility:

• Diet: The Harlequin Shrimp is an Obligate Carnivore that feeds exclusively on live starfish (sea stars). It will not accept prepared foods such as mysis, pellets, or flakes and will starve without a constant supply of echinoderms. This strict diet is the primary difficulty in its care.
• Feeding: A supply of live starfish (such as Asterina or chopped legs from a larger, non-toxic starfish like the Chocolate Chip Star) must be secured before purchasing. A pair of shrimp will consume a medium-sized starfish in 1–3 weeks. Uneaten decaying portions must be removed quickly to maintain water quality.
• Reef Compatibility: It is Reef Safe With Caution. While the shrimp is 100% safe with all corals, it will systematically hunt and kill all ornamental starfish (e.g., Linckia, Brittle, Serpent, and Sand-Sifting stars) and may occasionally consume sea urchins if starfish are scarce.
• Temperament: It is Peaceful toward fish, but will be territorial toward other Harlequin Shrimp (unless a bonded pair) and other shrimp species. They should be housed with peaceful fish only, as large or aggressive fish (e.g., Triggerfish, Puffers, Lionfish) will easily prey on the small, delicate shrimp.
• Housing: Requires highly stable, pristine water quality (low nitrates and no copper). Provide ample live rock, caves, and crevices for hiding, as they are often shy. Slow drip acclimation is crucial due to their sensitivity.

Quick Facts

• Scientific Name: Hymenocera picta
• Primary Common Name: Harlequin Shrimp
• Other Common Names: Painted Shrimp, Clown Shrimp
• Origin: Indo-Pacific
• Max Size: 1.5-2 inches (4-5 cm)
• Temperament: Peaceful (but an obligate predator of starfish)
• Diet: Obligate Carnivore (Eats only live starfish)
• Minimum Tank Size: 10+ Gallons (Nano-Tank Suitable)
• Reef Compatibility: With Caution (Will eat all ornamental starfish)