 They feed by filtering sand through their mouthparts, leaving behind balls of sand that are disintegrated by the incoming high tide.Sand bubbler crabs are small crabs, around across the carapace, and they are characterised by the presence of "gas windows" on the merus of the legs; in "Dotilla", these windows are also present on the thoracic sternites.A similar system has evolved in parallel in the porcelain crab genus "Petrolisthes".