Sleepy Sponge Crab

Tumidodromia dormia

The Sleepy Sponge Crab, known scientifically as Tumidodromia dormia, is the largest species within the family Dromiidae. It can be identified by its carapace, which can grow up to 20 cm wide, making it the largest of its kind. The carapace is rounded and covered with dense pubescence, featuring five anterolateral teeth with the median ones being the largest. Its coloration is predominantly light brown with distinctive pink fingers. This species is known for its unique behavior of camouflaging itself by carrying sponges or other materials like wood or discarded shoes on its back, held in place by its last two pairs of legs. The Sleepy Sponge Crab inhabits the shallow waters of the Indo-Pacific region, ranging from East Africa and the Red Sea to Hawaii and French Polynesia. It is typically found at depths between 5 and 112 meters, preferring rocky-muddy substrates often near reefs. This crab is benthic and is most commonly found in moderately shallow waters. It is omnivorous, with a diet that includes sea stars and possibly other small invertebrates. Divers encountering the Sleepy Sponge Crab may find it sheltering under old bivalve shells or camouflaged with sponges on its back. Its conservation status has not been evaluated, and it is considered a minor commercial species in fisheries.