Common Xenia Coral Shrimp

Hippolyte commensalis

Kingdom: Animalia
Phylum: Arthropoda
Subphylum: Crustacea
Class: Malacostraca
Order: Decapoda
Family: Hippolytidae
Genus: Hippolyte
Species: Hippolyte commensalis

The common Xenia coral shrimp (Hippolyte commensalis) is a tiny, highly variable shrimp that lives on soft corals and comes in many colour forms. Shrimps once described as separate species, the marbled soft coral shrimp (Alcyonohippolyte brachycarpus), the freckled soft coral shrimp (A. maculata) and the striped Xenia coral shrimp (A. tenuicarpus), are now all treated as this one species.

It is usually under 1 cm long. Its colour and pattern match its host: marbled forms live on Sarcophyton and similar leather corals, freckled forms are covered in spots that mimic polyps, and striped forms on Xenia carry lines that follow the pulsing polyps. It feeds on mucus and particles from its soft coral host.

In the Philippines this shrimp is common on Xenia and other soft corals on reefs and slopes, but its camouflage makes it easy to miss. A slow look among the polyps with a macro lens will often reveal one.