''Geosesarma'' is genus of small

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

terrestrial crab A number of lineages of crabs have evolved to live predominantly on land. Examples of terrestrial crabs are found in the families Gecarcinidae and Gecarcinucidae, as well as in selected genera from other families, such as '' Sesarma'', althou ...

s, typically less than across the

carapace A carapace is a dorsal (upper) 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 unde ...

. They live and reproduce on land with the larval stages inside the

egg An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on its own, at which point the ...

. They are found from

India India, officially the Republic of India, is a country in South Asia. It is the List of countries and dependencies by area, seventh-largest country by area; the List of countries by population (United Nations), most populous country since ...

, through

Southeast Asia Southeast Asia is the geographical United Nations geoscheme for Asia#South-eastern Asia, southeastern region of Asia, consisting of the regions that are situated south of China, east of the Indian subcontinent, and northwest of the Mainland Au ...

, to the

Solomon Islands Solomon Islands, also known simply as the Solomons,John Prados, ''Islands of Destiny'', Dutton Caliber, 2012, p,20 and passim is an island country consisting of six major islands and over 1000 smaller islands in Melanesia, part of Oceania, t ...

and

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

. In the pet trade, they are sometimes called vampire crabs. This has nothing to do with their feeding habits, but rather with the bright, contrastingly yellow eyes of some ''Geosesarma'' species.

Species

''Geosesarma'' contains these species: *'' Geosesarma aedituens'' Naruse & Jaafar, 2009 *'' Geosesarma albomita'' Yeo & Ng, 1999 *''

Geosesarma ambawang ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Ng, 2015 *'' Geosesarma amphinome'' (De Man, 1899) *'' Geosesarma anambas'' Ng, Wowor & Yeo, 2023 *'' Geosesarma angustifrons'' (A. Milne-Edwards, 1869) *''

Geosesarma araneum ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' (Nobili, 1899) *''

Geosesarma aurantium ''Geosesarma'' is genus of small freshwater crab, freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the crustacean larvae, larval stages inside the egg (biology), egg. They are found f ...

'' Ng, 1995 *''

Geosesarma batak ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Manuel-Santos, Ng & Freitag, 2016 *''

Geosesarma bau ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Ng & Jongkar, 2004 *''

Geosesarma bicolor ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Ng & Davie, 1995 *''

Geosesarma bintan ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' T. M. Leong, 2014 *''

Geosesarma cataracta ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Ng, 1986 *''

Geosesarma celebense ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' (Schenkel, 1902) *''

Geosesarma clavicrure ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' (Schenkel, 1902) *''

Geosesarma confertum ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' (Ortmann, 1894) *''

Geosesarma danumense ''Geosesarma danumense'' is a species of crab found in from Sabah, Malaysia. References Sesarmidae Freshwater crustaceans of Asia Crustaceans described in 2002 Taxa named by Peter Kee Lin Ng {{Eubrachyura-stub ...

'' Ng, 2003 *'' Geosesarma dennerle'' Ng, Schubart & Lukhaup, 2015 *'' Geosesarma foxi'' (Kemp, 1918) *'' Geosesarma gordonae'' (Serène, 1968) *'' Geosesarma gracillimum'' (De Man, 1902) *'' Geosesarma hagen'' Ng, Schubart & Lukhaup, 2015 *'' Geosesarma hednon'' Ng, Liu & Schubart, 2003 *'' Geosesarma ianthina'' Pretzmann, 1985 *'' Geosesarma insulare'' Ng, 1986 *'' Geosesarma johnsoni'' (Serène, 1968) *'' Geosesarma katibas'' Ng, 1995 *'' Geosesarma krathing'' Ng & Naiyanetr, 1992 *'' Geosesarma larsi'' Ng & Grinang, 2018 *'' Geosesarma lawrencei'' Manuel-Santos & Yeo, 2007 *'' Geosesarma leprosum'' (Schenkel, 1902) *'' Geosesarma maculatum'' (De Man, 1892) *'' Geosesarma malayanum'' Ng & Lim, 1986 *''

Geosesarma mirum ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Shy & Ng, 2019 *'' Geosesarma nannophyes'' (De Man, 1885) *'' Geosesarma nemesis'' Ng, 1986 *'' Geosesarma nigripes'' Ng & Wowor, 2024 *'' Geosesarma noduliferum'' (De Man, 1892) *'' Geosesarma notophorum'' Ng & C. G. S. Tan, 1995 *'' Geosesarma ocypodum'' (Nobili, 1899) *'' Geosesarma penangense'' (Tweedie, 1940) *'' Geosesarma peraccae'' (Nobili, 1903) *'' Geosesarma protos'' Ng & Takeda, 1992 *'' Geosesarma rathbunae'' (Serène, 1968) *''

Geosesarma riani ''Geosesarma'' is genus of small freshwater or terrestrial crabs, typically less than across the carapace. They live and reproduce on land with the larval stages inside the egg. They are found from India, through Southeast Asia, to the Solomon ...

'' Ng & Wowor, 2024 *'' Geosesarma rouxi'' (Serène, 1968) *'' Geosesarma sabanum'' Ng, 1992 *'' Geosesarma sarawakense'' (Serène, 1968) *'' Geosesarma scandens'' Ng, 1986 *'' Geosesarma serenei'' Ng, 1986 *'' Geosesarma solomonense'' (Serène, 1968) *'' Geosesarma starmuhlneri'' Pretzmann, 1984 *'' Geosesarma sumatraense'' Ng, 1986 *'' Geosesarma sylvicola'' (De Man, 1892) *'' Geosesarma ternatense'' (Serène, 1968) *'' Geosesarma teschi'' Ng, 1986 *'' Geosesarma thelxinoe'' (De Man, 1908) *'' Geosesarma tiomanicum'' Ng, 1986 *'' Geosesarma vicentense'' (Rathbun, 1914) As of March 2015, professor Peter Ng of National University of Singapore has named 20 ''Geosesarma'' species, and he "has another half a dozen or so newly collected ''Geosesarma'' species from Southeast Asia in his lab, and these species still need to be named and described."

Threats

'' Geosesarma dennerle'' and '' Geosesarma hagen'', both originally from

Java Java is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea (a part of Pacific Ocean) to the north. With a population of 156.9 million people (including Madura) in mid 2024, proje ...

, are threatened by illegal overcollection for the aquarium trade.

References

{{Taxonbar, from=Q311106 Sesarmidae Terrestrial crustaceans Taxa named by Johannes Govertus de Man