The most abyssal of all crabs yet known is Ethusina abyssicola, Smith, or what is perhaps only a variety of it, E.
They have a well-developed proboscis which is used as a suctorial organ; some are abyssal, but the majority are either commensals or parasites of Echinoderms.
Dimya; recent in abyssal depths and fossil since the Jurassic.
North Atlantic and Mediterranean; various abyssal species.
They inhabit chiefly the northern seas, but many abyssal forms occur between the tropics and in the southern parts of the Atlantic and Pacific. They are represented in British waters by eight genera, and about twenty species, only one of which, the burbot (Lola vulgaris), is an inhabitant of fresh waters.