of nearly 50 cm 0 abbr=on. Giant isopods lack an obvious carapace (shell), which is reduced to a "cephalic shield" covering only the head. This means that the gill-like structures, which in other related groups are protected by the carapace, are instead found on specialised limbs on the abdomen.

The dorsal (upper) surface of the animal is covered by a series of overlapping, articulated plates which give protection while also