In this closeup of the face the small spinelike rostrum can be seen. Other features include the spine-tipped tubercles on the dorsal carapace and on the dorsal surfaces of the legs and chelae. Note that in Anomuran crabs the second antennae are based lateral to the eyes, as can be seen here. Photo by Will Duguid.
The abdomens of adult males and females differ in several ways. This is the abdomen of a female, which is shown above, is broader than that of a male and is asymmetrical. The plates on the left side of the female abdomen (to the right above) are larger than those on the left. The right side of the female abdomen also has a row of small marginal plates but the left side does not. The female also has pleopods on her abdomen, which cannot be seen without pulling the abdomen away from the thorax.
This photo helps illustrate why these crabs are called box crabs. When disturbed they fold their legs and abdomen together and hold them tightly against the body so that they are like a tight box or ball. The crabs on the left of the seat are upright while those to the left are upside-down. Photo by Will Duguid
Lopholithodes foraminatus caught by Joe Watson of Campbell River BC at 110-130 m depth in a crab trap near Twin Island in the Strait of Georgia, Canada. This is a large male. The distinctive foramen created by the legs can be seen to the left, between the base of the chela and the next leg, lined with smooth purple and white cuticle. (Photo by: Will Duguid, University of Victoria)
Brown Box Crab - Lithodes Foramenutus Photographed on site at The Field Museum, Chigaco, for the Encyclopedia of Life project. Thanks to Alta Buden for making it all happen and to Jochen Cerber for allowing access to the crustacea specimensPhotosynthImages collection
