Hairy Squat Lobster (Lauriea siagiani)

Batu Lubang Besar, Lembeh.
They can be less than one inch to about 4 inches in length, depending upon the species. Squat lobsters have 10 legs. The first pair of legs are very long and contain claws. The three pairs of legs after that are used for walking. The fifth pair has small claws and may be used for cleaning gills. This fifth pair of legs is much smaller than the legs in "true" crabs. Squat lobsters have a short abdomen that is folded under their body.
Squat lobsters are in the infraorder Anomura - many of the animals in this infraorder are called "crabs," but they are not true crabs. They aren't lobsters, either. In fact, squat lobsters are more closely related to hermit crabs than to lobsters. More info here:
https://www.thoughtco.com/squat-lobsters-profile-2291811
http://www.digitaljournal.com/blog/20406