Description
Lybia tessellata, commonly known as the pom-pom crab, boxer crab, or mosaic boxer crab, is a tiny marine crustacean belonging to the family Xanthidae.
Physical Description
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Size: Reaches an adult width of about 2 to 2.5 cm (roughly 1 inch).
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Carapace: Trapezoid in shape, featuring a distinct stained-glass or geometric mosaic pattern of dark lines over a white, cream, or beige background.
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Limbs: Slim chelipeds (claws) armed with small spines, paired with slender, banded walking legs.
Key Behavior & Symbiosis
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Pom-Pom Habit: It carries a small sea anemone (commonly Triactis producta or Bunodeopsis species) in each claw, waving them like pom-poms or boxing gloves.
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Defense & Feeding: The anemones are equipped with stinging cells (nematocysts) that deter predators. Because the crab's modified claws prevent it from feeding itself directly, it uses the anemones to trap food particles from the water column and scrapes a portion off with its mouthparts (maxillipeds).
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Moulting: When the crab outgrows its exoskeleton, it temporarily puts the anemones down in a safe spot, completes its moult, and immediately picks them back up.
Habitat & Distribution
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Geographic Range: Found across the shallow tropical Indo-Pacific region, ranging from the Red Sea and East Africa to Indonesia, New Guinea, Japan, and Hawaii.
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Environment: Inhabits coral reefs, rocky areas, and sandy or gravelly seabeds at depths typically under 20 to 40 meters
