Chiromantes haematocheir
Encyclopedia
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 heamotocheir and Sesarma heamotocheir. It is quite distinct from the other species placed in the genus Chiromantes, and the genus may be restricted to this one species.
with a smooth surface and irregular stripes along the sides. Males have large, smooth chela
e 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.
, this variety of C. haematocheir can be found in Nagano prefecture where elevations often exceed 600 metres (1,968.5 ft) above sea level, and distances to the ocean can be over 80 kilometres (49.7 mi). This indicates that they are freshwater crabs, probably living in forest streams (if they live in water at all).
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
of the family Sesarmidae
Sesarmidae
Sesarmidae is a family of crabs, previously included in the Grapsidae by many authors. Several species, namely in Geosesarma, Metopaulias and Sesarma, are true terrestrial crabs. They do not need to return to the sea even for breeding.-Genera:...
(subfamily Sesarminae), which is endemic to East Asia
East Asia
East Asia or Eastern Asia is a subregion of Asia that can be defined in either geographical or cultural terms...
. It is known under the common names red-clawed crab or akategani (Japanese
Japanese language
is a language spoken by over 130 million people in Japan and in Japanese emigrant communities. It is a member of the Japonic language family, which has a number of proposed relationships with other languages, none of which has gained wide acceptance among historical linguists .Japanese is an...
) and the Latin names Grapsus heamotocheir and Sesarma heamotocheir. 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 carapaceCarapace
A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...
with a smooth surface and irregular stripes along the sides. Males have large, smooth chela
Chela
Chela has two main meanings. One derivation comes from Hindi from Sanskrit , meaning "slave" or "servant". In English, the word means a religious student or disciple...
e with curved claws. The color of these crabs varies throughout their development; juvenile
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
crabs typically have a white or yellow carapace, while adults are usually crimson
Crimson
Crimson is a strong, bright, deep red color. It is originally the color of the dye produced from a scale insect, Kermes vermilio, but the name is now also used as a generic term for those slightly bluish-red colors that are between red and rose; besides crimson itself, these colors include...
red.
Mountain crabs
Known as "yama-gani" in JapanJapan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, this variety of C. haematocheir can be found in Nagano prefecture where elevations often exceed 600 metres (1,968.5 ft) above sea level, and distances to the ocean can be over 80 kilometres (49.7 mi). This indicates that they are freshwater crabs, probably living in forest streams (if they live in water at all).