Metasesarma obesum

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Metasesarma obesum, also known as the marble crab or marble Batik crab, is a small semiterrestrial crab in the Sesarmidae family. It lives on sandy beaches in brackish water along the Indian and Pacific Oceans. The neotype is a male about 14.3 mm by 13.5 mm. These crabs are sometimes kept in aquariums. In captivity they need land, hiding places such as leaf litter or driftwood, and access to shallow brackish or salt water. They are omnivorous and usually peaceful with tank mates, but may fight with conspecifics if space is limited.