| Deckenia | |
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| Deckenia imitatrix | |
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| Genus: | Deckenia Hilgendorf, 1869 |
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Deckenia is a genus of freshwater crabs from East Africa, in the family Potamonautidae, [1] or sometimes in a family of its own, Deckeniidae. [2] The genus was named by Hilgendorf after Karl Klaus von der Decken who collected the first examples during his expeditions to Africa. Both species live in swamps from Eyl in Somalia to Dar es Salaam, Tanzania, both in coastal areas and further inland. [2] A third species, Deckenia alluaudi, lives in the Seychelles, and has been transferred to a separate genus, Seychellum . [3]
Deckenia imitatrix is found in the coastal plains between Kenya and Somalia. [2] It is threatened by habitat loss, and is listed as Near Threatened on the IUCN Red List. [4]
Deckenia mitis is found in a few places in Kenya, and more widely in Tanzania from the eastern coastal lowlands to the western Wembere Steppe, and south to near Lake Malawi. [2] It is threatened by habitat loss, and is listed as Near Threatened on the IUCN Red List. [5]
Afrithelphusa is a genus of freshwater crabs in the family Potamonautidae. It contains four species, all of which were formerly listed as critically endangered by the International Union for Conservation of Nature (IUCN). They are all endemic to the Upper Guinean forests of Guinea and Sierra Leone.
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.
Louisea is a genus of freshwater crab in the family Potamonautidae, containing two species, Louisea balssi and Louisea edeaensis. Both species are endemic to Cameroon and listed as endangered species on the IUCN Red List.
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.
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).
Platythelphusa is a genus of freshwater crabs endemic to Lake Tanganyika. It has been placed in a number of families, including a monotypic family, Platythelphusidae, as well as Potamidae and its current position in the Potamonautidae, and has also been treated as a subgenus of Potamonautes. It forms a monophyletic group, possibly nested within the genus Potamonautes, which would therefore be paraphyletic. The genus is the only evolutionary radiation of crabs to have occurred in a freshwater lake, and it occurred recently, probably since the Pliocene. This parallels the better known radiation of cichlid fishes in Lake Tanganyika. Only one other species of freshwater crab is found in Lake Tanganyika, Potamonautes platynotus.
Potamonautes is a genus of African freshwater crabs in the family Potamonautidae. It is both the most widespread and most diverse genus of African freshwater crabs, including more than half the species of this continent. They are found in most freshwater habitats of the African mainland and some species are semi-terrestrial.
Potamonautes platycentron is a species of freshwater crab in the family Potamonautidae, which is endemic to Lake Chala in Kenya and Tanzania. It was originally described by Franz Martin Hilgendorf in 1897, as Telphusa platycentron.
Potamonautes raybouldi is a species of freshwater crab. It lives in water-filled tree holes in forests in the eastern Usambara Mountains of Tanzania and the Shimba Hills in Kenya. It is threatened by deforestation resulting from the expansion of the human population, and is listed as a vulnerable species on the IUCN Red List. The species was described in 2004, and named after Professor John N. Raybould of the University of Bristol, who collected the first specimens of the species.
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:
Potamonautidae is a family of freshwater crabs endemic to Africa, including the islands of Madagascar, the Seychelles, Zanzibar, Mafia, Pemba, Bioko, São Tomé, Príncipe and Sherbro Island. It comprises 18 extant genera and 138 extant species. Fossil remains dating from the Late Miocene period have been attributed to the family Potamonautidae.
Hainanpotamon vietnamicum is a species of crab. Originally described as a species of Geothelphusa, it is now treated as part of the genus Hainanpotamon, although it has also been suggested as a member of Tiwaripotamon. It is only known from a single locality in Cúc Phương National Park, Ninh Bình Province, Vietnam.
Johora singaporensis, the Singapore stream crab or Singapore freshwater crab, is a critically endangered species of freshwater crab endemic to Singapore. It grows to a size of 30 millimetres (1.2 in) wide.
Disparithelphusa pecki is a species of freshwater crab in the family Pseudothelphusidae, and the only species in the genus Disparithelphusa.
Neoepilobocera gertraudae is a species of cave-dwelling crab from Cuba.
Around 1,300 species of freshwater crabs are distributed throughout the tropics and subtropics, divided among eight families. They show direct development and maternal care of a small number of offspring, in contrast to marine crabs, which release thousands of planktonic larvae. This limits the dispersal abilities of freshwater crabs, so they tend to be endemic to small areas. As a result, a large proportion are threatened with extinction.
Seychellum alluaudi is a species of freshwater crab endemic to the Seychelles, and the only true freshwater crab in that country. It lives in rainforest streams on the archipelago's granitic high islands. Although it may be abundant, little is known about its biology. If its habitat were to decline in quality, S. alluaudi might become endangered, but it is currently listed as Vulnerable on the IUCN Red List.
Migmathelphusa olivacea is a species of freshwater crab found in Lake Poso on the Indonesian island of Sulawesi. It is the only species in its genus. It is listed by the IUCN as Endangered, given "its extent of occurrence and area of occupancy is less than 500 square kilometres (190 sq mi)", and its individuals being found in less than five locations. There is also a "decline in the extent and quality of its habitat and it is not found in a protected area". Being found around a lake, "present and future threats to this species include human-induced habitat loss/degradation due to population increases and industrial and agrarian development".
Johora thaiana is a species of freshwater crab described from specimens found in Thailand, as the name was derived. Most species in this genus are found in Singapore and Peninsular Malaysia so this is the most northern species of the genus. The crab is completely aquatic and can be found under rocks or vegetation in flowing streams and adjacent pools. However, they tend to inhabit sheltered habitats with slower water. They are active more at night.
Daipotamon minos is a cavernicolous freshwater crab species found in a single limestone cave near La Tai village in Libo county, Guizhou province at an altitude of about 600 m above sea level, where it inhabits slowly flowing or stagnant parts of a subterranean river. It is the only species of the genus Daipotamon.