Harlequin Serpent Starfish

Serpent Starfish, otherwise commonly known as brittle stars, can be a great addition to nearly any home aquarium. Sharing many similarities to regular starfish, these animals are primarily scavengers, feeding on a variety of detritus ranging from particulate material and bacteria to frozen food scraps. Unlike their true starfish cousins, Serpent Starfish use their thin wiry bodies to fit themselves into tight crevices of the rockwork, venturing out only in search of food. Additionally, Serpent Starfish contain all of their organs inside of their central disk and cannot regrow the main body from a fragmented arm.

***Serpent Starfish are more fragile than true starfish and are far more prone to detaching their arms when distressed; It is highly recommended to keep handling to a minimum with these starfish.

Quick Care Guide

Care Level: Moderate
Minimum Tank Size: 30 gallons
Temperament: Peaceful
Diet: Carnivorous Scavenger
Reef Safe: Yes
Adult Size: Arm span up to about 8 inches
Region: Caribbean and Western Atlantic
Scientific Name: Ophioderma appressum

About the Harlequin Serpent Star

The Harlequin Serpent Starfish, also called the harlequin brittle star, is named for the light and dark bands that ring each of its five smooth, flexible arms. Its central disc is usually mottled in brown, gray, or olive, and each individual’s pattern is slightly different.

Unlike the larger green brittle star (Ophiarachna incrassata), which is known to catch small fish, the Harlequin Serpent Star is a scavenger that is peaceful toward fish.

Tank Requirements

Choose a mature aquarium with plenty of rockwork and shaded crevices. This starfish hides by day with only an arm or two visible, then moves out across the rock and sand at night. Cover overflow openings and pump intakes, since brittle stars can squeeze into surprisingly small gaps.

Diet and Feeding

Serpent stars scavenge detritus and leftover food, but they should also be fed directly. Place small pieces of mysis, chopped seafood, or sinking pellets near an exposed arm two to three times per week, and it will pass the food along its arm to its mouth.

Temperament and Tankmates

The Harlequin Serpent Starfish is peaceful with fish, corals, and most invertebrates. Avoid harlequin shrimp, which eat starfish, as well as triggerfish, puffers, and large wrasses that may pick at its arms.

Reef Compatibility

This species is reef safe. It does not eat corals, and its nighttime scavenging helps clean up uneaten food in hard-to-reach places.

Water Parameters

Temperature: 75–80°F
Specific Gravity: 1.024–1.026
pH: 8.1–8.4
Alkalinity: 8–12 dKH

Echinoderms are very sensitive to changes in salinity. Drip acclimate over at least an hour and keep specific gravity steady. Invertebrates are highly sensitive to copper, and copper-treated water or medications should never be added to an aquarium that houses them.

Common Considerations

• Handle as little as possible: Brittle stars readily drop arms when stressed. Lost arms regrow slowly.

• Acclimate very slowly: Rapid salinity changes are the most common cause of losses.

• Expect a night owl: It will hide most of the day, especially at first.

• Keep away from harlequin shrimp: They are specialized starfish predators.