Ceylonthelphusa alpina is a species of freshwater crabs in the family Gecarcinucidae. The species is endemic to Sri Lanka, and is classed as an endangered due to habitat degradation.
Ceylonthelphusa is a genus of freshwater crabs endemic to Sri Lanka, where they live in moist lowland forests, swamps and rivers. Many of the species are on the IUCN Red List of threatened species, with the greatest risk factor being habitat loss. Ceylonthelphusa contains these species:
Ceylonthelphusa armata is a species of freshwater crabs in the family Gecarcinucidae. The species is endemic to Sri Lanka, and is classed as an endangered due to habitat degradation.
Ceylonthelphusa callista is a species of freshwater crabs in the family Gecarcinucidae. The species is endemic to areas of Sri Lanka, such as Knuckles Mountain Range and Mahaweli River.
Clinothelphusa kakoota is a species of crab in the family Gecarcinucidae, which is endemic to Sri Lanka. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical swamps, and rivers. It is threatened by habitat loss, and is listed as a critically endangered species on the IUCN Red List. It is known from a single site with an area of less than 100 km2 (39 sq mi). Its nearest relatives are another Sri Lankan endemic genus of crabs, Ceylonthelphusa.
Mahatha is a genus of freshwater crabs endemic to Sri Lanka. Four of the six species are critically endangered due to habitat loss, and two are listed as Least Concern on the IUCN Red List.
Oziotelphusa hippocastanum is a species of crustacean in the family Parathelphusidae. It is endemic to Sri Lanka. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical swamps, and rivers. It is threatened by habitat loss.
Pastilla dacuna is a species of freshwater crab in the monotypic genus in the family Gecarcinucidae. It is endemic to Sri Lanka. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical swamps, and rivers. It is threatened by habitat loss.
Perbrinckia is a genus of freshwater crabs of the family Gecarcinucidae that is endemic to Sri Lanka, named after Per Brinck. Its natural habitats are subtropical or tropical moist lowland forests, subtropical or tropical swamps, and rivers. It contains 14 species, most of which are included on the IUCN Red List as critically endangered species (CR) or vulnerable species (VU) because they are threatened by habitat loss; only one species is of least concern (LC).
Spiralothelphusa is a genus of freshwater crabs in the family Gecarcinucidae. It contains these species, all of which are included on the IUCN Red List:
Oziotelphusa ceylonensis is a species of freshwater crabs in the family Parathelphusidae. It is endemic to Sri Lanka. The species is not threatened in their habitats, where they observed to be survive well in man-made settlements as well. The species was discovered from nine localities around Kandy hills. The preferred habitats are embankments of paddy fields, where many irrigation canals constructed to provide continuous supply of water to the field.
Oziotelphusa ritigala is a species of freshwater crabs in the family Gecarcinucidae. It is endemic to Sri Lanka. The species is categorized as vulnerable by IUCN Red List due to less abundance is observed localities and much restricted ecology.
Oziotelphusa stricta is a species of freshwater crabs in the family Gecarcinucidae. It is endemic to Sri Lanka. The species was initially categorized as Near Threatened by the finders, but recent observations included to vulnerable by IUCN Red List due to less abundance is observed localities and much restricted ecology.
The Sri Lanka tree crab,, is a species of freshwater crabs of the family Gecarcinucidae that is endemic to Sri Lanka. It is the only known tree climbing freshwater crab found in the country. The crab is discovered from 11 localities from Sri Lanka throughout Kalu River, Walawe River and Gin River basins. Adult are known to survive well in rainwater-filled tree hollows of trees such as Shorea sp., Artocarpus sp., Dillenia sp., Garcinia sp., Myristica sp., and Gyrinops walla. Females with youngs can be seen during February and March on the ground, never within tree hollows. The known predators are Greater coucal, White-throated kingfisher, Sri Lanka grey hornbill and Eurasian otter.
India (Tamil Nadu)
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Sri Lanka 
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