Chiromantes haematocheir
Chiromantes haematocheir is a mudflat crab of the family Sesarmidae (subfamily Sesarminae), which is endemic to East Asia. It is known under the common names red-clawed crab or "akategani" (Japanese) and the Latin names "Grapsus haematocheir" and "Sesarma haematocheir". It is quite distinct from the other species placed in the genus "Chiromantes", and the genus may be restricted to this one species. Description. "C. haematocheir" has a square carapace with a smooth surface and irregular stripes along the sides. Males have large, smooth chelae with curved claws. The color of these crabs varies throughout their development; juvenile  crabs typically have a white or yellow carapace, while adults are usually crimson red. Mountain crabs. Known as "yama-gani" in Japan, this variety of "C. haematocheir" can be found in Nagano prefecture where elevations often exceed above sea level, and distances to the ocean can be over . This indicates that they are freshwater crabs, probably living in forest streams (if they live in water at all).