Pom pom crab (Lybia tessellata) care guide

Group

Other invertebrates

Other names

Boxer crab, Cheerleader crab, Mosaic boxer crab, Melia tessellata

Family

Xanthidae

Origin

Shallow tropical Indo-Pacific, from the Red Sea and East Africa to Indonesia, New Guinea, Japan and Hawaii

Water

saltwater

Maximum size

2.5 cm

Temperature

22–26°C

pH

8.1–8.4

Hardness

dKH 8–12, SG 1.020–1.025

Care level

beginner

Temperament

peaceful

Reef safe

with_caution

Care

The pom pom crab is a tiny Indo-Pacific crab, about 2.5 cm across, famous for carrying a small sea anemone in each claw like a cheerleader's pom-poms. Its trapezoid shell is divided by dark lines into coloured patches like stained glass, and its legs are banded with white speckles. The anemones are usually Bunodeopsis or Triactis producta. When threatened it waves them at the attacker, whose stinging cells defend the crab, and it uses their tentacles to gather food because its own claws are too slender to feed with. In the wild it lives on sand, gravel and live coral in shallow water. In the aquarium it suits a nano or reef tank with rock and crevices, where it shelters and is often shy. Keep it with small, peaceful tankmates so it is not outcompeted for food. If it loses its anemones it may split one to make two, or take another small anemone. It is sensitive to copper and poor water quality and moults like any crab, hiding while its new shell hardens. It helps clean the tank by sweeping up detritus and leftover food with its anemones. Copper-based medicines and some plant fertilisers are toxic to shrimp, snails and most invertebrates. Sources: LiveAquaria (liveaquaria.com/products/pom-pom-crab); Wikipedia (en.wikipedia.org/wiki/Lybiatessellata). Checked October 2026.

Diet

An omnivore that feeds through its anemones: it dabs them on rock and sand to collect detritus and food particles and passes them to its mouthparts. Offer small meaty foods such as mysis, finely chopped fish and clam, and fine frozen foods placed near its hiding place; a little food also keeps its anemones healthy.

Breeding

Females carry red eggs under the abdomen until they hatch. The larvae are planktonic and are not raised in home aquaria. Sexes can be told apart by the shape of the underside flap (narrow in males, broad in females).

Compatibility and tank mates

Generally reef safe, but its anemones could sting sessile invertebrates and corals they are pressed against; the risk is small because the anemones are tiny. Peaceful towards fish and other invertebrates. Larger crabs, hermits, wrasses, hawkfish and other predators may eat it or steal its food.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.