Facts About Harlequin Shrimp

One of the most beautiful tropical shrimp is the Harlequin shrimp. Known as the flowers of the shrimp family, Harlequin shrimp---sometimes called clown or dancing shrimp---exhibit brilliant purple or blue polka-dot markings on their white bodies and blue and white stripped legs.

  1. Description

    • The two known species of Harlequin shrimp are Hymenocera elegans and Hymenocera picta. The differences between the two are slight, but the picta appear to have more purple and even some orange hues in their coloration. Both range in size from 1 to 2 inches long.

    Habitat

    • Hymenocera elegans live throughout the Indian Ocean and in Pacific Ocean where the two water bodies join, while the Hymenocera picta is specific to Hawaii. Harlequin shrimp live in coral reefs, preferring a temperature range of 72 to 82 degrees Fahrenheit. They are rare, and damage to their coral reef habitat affects their population.

    Diet

    • Harlequin shrimp are predatory and require a specific diet of starfish and some sea urchins for long-term survival. Locating their prey by scent, the shrimp pries the starfish from its anchoring rock or reef. Often, two shrimp, a male and a female, join forces to overturn the starfish together and share the meal. They turn the starfish onto its back and eat the delicate tube feet, keeping the starfish alive for three or four days (sometimes by feeding it) throughout the eating process. Sometimes they eat an entire starfish much larger than themselves.

    Behavior

    • The Harlequin moves slowly and waves its two large pincers even when stationary. While its exceptional coloration may warn away predators, the shrimp also may incorporate toxins from its prey, making it distasteful or dangerous for its predators to eat.

    Reproduction

    • Females typically are larger than males and have colored abdominal plates. Males' abdominal plates are white. Mating after the female's molt (shedding her shell), the female produces between 100 to 5,000 eggs per season depending on environmental factors. She tends and cleans them until they hatch. Mating for life, a monogamous shrimp pair becomes territorial.

    Aquarium Life

    • Harlequin shrimp can be kept in aquariums as small as 10 gallons, but are difficult to keep since they do not adapt to captivity well, possibly due to dietary restrictions (primarily starfish). They are also sensitive to changes in both gravity and pH levels.