Nanhaipotamon

These crabs are relatively large, with a carapace breadth of up to {{convert|50|mm|abbr=on}}. Depending on the species, the carapace may be vividly coloured, especially in males of N. hongkongense (orange to red), N. aculatum (dark blue) and N. zhuhaiense (light blue). Chelipeds are usually unequal, more so in larger males, where one cheliped is relatively much larger than the other. This may be of use in territorial fights, as the crabs are very aggressive towards conspecifics.

Crabs of the genus Nanhaipotamon inhabit the banks of small to medium-sized hill streams, paddy fields and swamps. Although not particularly a lowland species, they usually do not occur above approximately 500 meters above sea level. Most species are nocturnal, leaving their burrows at night to forage. Species belonging to this genus have been recorded from Hong Kong,{{Cite journal|last1=Dudgeon|first1=D.|last2=Ng|first2=P. K. L.|date=1992|title=The Potamidae and Parathelphusidae (Crustacea : Decapoda : Brachyura) of Hong Kong|journal=Invertebrate Systematics|volume=6|issue=3|pages=741–768|doi=10.1071/it9920741|s2cid=44187816 |issn=1447-2600}} Macau,{{Cite journal|last1=Huang|first1=Chao|last2=Wong|first2=Kai Chin|last3=Ahyong|first3=Shane T.|date=2018-12-20|title=The freshwater crabs of Macau, with the description of a new species of Nanhaipotamon Bott, 1968 and the redescription of Nanhaipotamon wupingense Cheng, Yang, Zhong & Li, 2003 (Crustacea, Decapoda, Potamidae)|url=https://zookeys.pensoft.net/article/30726/|journal=ZooKeys|issue=810|pages=91–111|doi=10.3897/zookeys.810.30726|issn=1313-2970|pmc=6308228|pmid=30613174|doi-access=free}} Guangdong, Fujian, Zhejiang, Taiwan and Dongyin Island.{{Cite journal|last1=Shih|first1=Hsi-Te|last2=Chen|first2=Guo-Xiao|last3=Wang|first3=Li-Min|date=2005-09-15|title=A new species of freshwater crab (Decapoda: Brachyura: Potamidae) from Dongyin Island, Matsu, Taiwan, defined by morphological and molecular characters, with notes on its biogeography|journal=Journal of Natural History|volume=39|issue=31|pages=2901–2911|doi=10.1080/00222930500214010|s2cid=53575560|issn=0022-2933|url=https://zenodo.org/record/5219964}}

Although crabs of the genus Nanhaipotamon are subject to the pet trade, not much is known about the population status of most species,{{Cite journal|last1=Hui|first1=Tommy Chung Hong|last2=Leven|first2=Michael Robertson|last3=Stanton|first3=David John|date=2018-01-26|title=Distribution of Nanhaipotamon hongkongense (Shen, 1940) (Crustacea: Brachyura: Potamidae), a freshwater crab endemic to Hong Kong|journal=Journal of Threatened Taxa|language=en|volume=10|issue=1|pages=11156–11165|doi=10.11609/jott.3619.10.1.11156-11165|issn=0974-7907|doi-access=free}} and many are only known from their respective type locality. Of the 18 currently accepted species, only three have meaningful IUCN assessments, the rest all being data deficient.{{Cite web|url=https://www.iucnredlist.org/en|title=The IUCN Red List of Threatened Species|website=IUCN Red List of Threatened Species|access-date=2019-05-20}} Nearly a third of known species were described in the last ten years, and yet there is evidence that a lot more may be discovered in the near future.{{Cite journal|last1=Huang|first1=Chao|last2=Mao|first2=Si Ying|date=2014-02-12|title=Two new potamid crabs, Yuexipotamon arcophallus new genus, new species and Minutomon shanweiense new genus, new species, (Crustacea: Decapoda: Brachyura: Potamidae) from southern China|journal=Zootaxa|volume=3764|issue=4|pages=455–466|doi=10.11646/zootaxa.3764.4.5|pmid=24870647|issn=1175-5334}} The gambling hub of Macau is one of the most densely populated places in the world, and a new species has been described there as recently as 2018. The rapid urbanization of coastal regions, habitat destruction, impacts on water quality and collection for consumption and the pet trade, pose serious threats to most known species.

Nanhaipotamon fujianense is known to be an intermediate host for the lung fluke species Paragonimus skrjabini.

• Nanhaipotamon aculatum Dai, 1997{{Cite web|url=https://www.researchgate.net/publication/285788709|title=A revision of freshwater crabs of the genus nanhaipotamon Bott, 1968 from China (Crustacea: Decapoda: Brachyura: Potamidae)|website=ResearchGate|access-date=2019-05-17}}
• Nanhaipotamon dongyinense Shih, Chen & Wang, 2005
• Nanhaipotamon formosanum (Parisi, 1916)
• Nanhaipotamon fujianense Lin, Cheng & Chen, 2013{{Cite journal|last1=Lin|first1=Guo-Hua|last2=Cheng|first2=You-Zhu|last3=Chen|first3=Shao-Hong|date=February 2013|title=[A new species of the genus Nanhaipotamon (Decapoda:Potamidae) serving as intermediate host of Paragonimus skrjabini]|journal=Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi = Chinese Journal of Parasitology & Parasitic Diseases|volume=31|issue=1|pages=39–42|issn=1000-7423|pmid=24812835}}
• Nanhaipotamon guangdongense Dai, 1997
• Nanhaipotamon hepingense Dai, 1997
• Nanhaipotamon hongkongense (Shen, 1940)
• Nanhaipotamon huaanense Dai, 1997
• Nanhaipotamon macau Huang, Wong & Ahyong, 2018
• Nanhaipotamon nanriense Dai, 1997
• Nanhaipotamon pinghense Dai, 1997
• Nanhaipotamon pingtanense Lin, Cheng & Chen, 2012{{Cite journal|last1=Lin|first1=Guo-Hua|last2=Cheng|first2=You-Zhu|last3=Chen|first3=Shao-Hong|date=2012-12-30|title=[A new species of the genus Nanhaipotamon (Decapoda: Potamidae) from China]|journal=Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi = Chinese Journal of Parasitology & Parasitic Diseases|volume=30|issue=6|pages=434–437|issn=1000-7423|pmid=23484252}}
• Nanhaipotamon pingyuanense Dai, 1997
• Nanhaipotamon wenzhouense Dai, 1997
• Nanhaipotamon wupingense Cheng, Yang, Zhong & Li, 2003
• Nanhaipotamon xiapuense Cheng, Li & Zhang, 2009{{Cite journal|last1=Cheng|first1=You-Zhu|last2=Li|first2=Li-Sa|last3=Zhang|first3=Yi|date=August 2009|title=[A new species of the genus Nanhaipotamon (Decapoda: Potamidae) from Xiapu County, Fujian]|journal=Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi = Chinese Journal of Parasitology & Parasitic Diseases|volume=27|issue=4|pages=368–369|issn=1000-7423|pmid=20067001}}
• Nanhaipotamon yongchuense Dai, 1997
• Nanhaipotamon zhuhaiense Huang, Huang & Ng, 2012{{Cite journal|last1=Ng|first1=Peter K. L.|last2=Huang|first2=Jian Rong|last3=Huang|first3=Chao|date=2012-12-17|title=A new species of Nanhaipotamon Bott, 1968 (Crustacea: Decapoda: Brachyura: Potamidae) from Zhuhai, Guangdong Province, China|journal=Zootaxa|volume=3588|issue=1|pages=55–63|doi=10.11646/zootaxa.3588.1.2|issn=1175-5334}}

File:Nanhaipotamon hongkongense island.jpg|alt=N. hongkongense from Hong Kong Island|Nanhaipotamon hongkongense

File:Nanhaipotamon hongkongense.jpg|alt=N. hongkongense hidden in crevice|Nanhaipotamon hongkongense

File:Nanhaipotamon aculatum 1.jpg|alt=N. aculatum hiding in its burrow|Nanhaipotamon aculatum

File:Nanhaipotamon aculatum 2.jpg|alt=N. aculatum hiding in burrow|Nanhaipotamon aculatum

File:Nanhaipotamon guangdongense.jpg|alt=Nanhaipotamon guangdongense from Zhuhai|Nanhaipotamon guangdongense

{{Reflist}}

• {{Commons category-inline|Nanhaipotamon|Nanhaipotamon}}
• {{Wikispecies-inline|Nanhaipotamon|Nanhaipotamon}}

{{Taxonbar|from=Q18585665}}

Category:Potamoidea

Category:Freshwater crustaceans of Asia

Category:Decapod genera