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Cambarus is a large and diverse genus of North American crayfish. The adults range in size from about 5 cm (2 in) up to approximately 15 cm (6 in).

Chattooga River Crayfish (14174938652).jpg
Cambarus scotti
Scientific classification

Erichson, 1846
Type species
Astacus Bartonii
Fabricius, 1798 [1]


The genus Cambarus is the second largest freshwater crayfish genus inhabiting the Northern Hemisphere, with only sixty fewer species than the genus Procambarus[2]. Though Cambarus are varied across species, the two terminal elements that make up the male form I gonopod form ninety degree angles with the central appendage, allowing for their identification. Unlike the genus Procambarus whose first pleopod tends to have three processes at the tip, Cambarus has only one or two[2]. Cambarus reach 17-26 mm carapace lengths in their first year, while average adult carapace length ranges from 55-62 mm[3].

As a genus containing nearly 100 species, Cambarus's coloration is variable[4]. Cambarus bartonii is dark brown, while species like Cambarus pauleyi range from subtle to vibrant blues and reds[2].


Most species of Cambarus are distributed along North America's eastern coast, extending from New Brunswick to northern Florida[2]. However, the genus extends as far westward as the Rocky Mountains of Wyoming and Colorado, inhabiting a variety of freshwater environments[5]. Devil crayfish (Cambarus diogenes) are perhaps the most widespread species in the genus, having been found in thirty states spanning approximately 2 million kilometers[5]. Though, most species of Cambarus are not so widely distributed[3].


Cambarus occupy a range of freshwater environments including streams, rivers, lakes, and burrows. Burrowing species of the genus include Cambarus dubius[2]. Cambarus also include many cave-dwelling species, both troglobites and troglophiles[3]. While salinity and temperature changes minimally affect Cambarus, the genus has shown an intolerance to anthropogenic pollution[6].



Like other crayfish, Cambarus are foragers. Diets are largely plant-based, though Cambarus also consume small marine organisms like molluscs, larvae, tadpoles and amphibian eggs. Cambarus also consume small rodents or birds when available[3]. In their first year, Cambarus typically consume 1-4% of their overall body-weight each day [3]. The genus is central to many freshwater food webs as they help maintain water quality through consumption of algae[6].


One of the largest crayfish genera, Cambarus includes a sizable number of vulnerable species [6]. Cave-dwellers like Cambarus jonesi are at risk due to their lack of genetic diversity and low population count. Other species like Cambarus veteranus are at risk due to human practices like logging and mining, which increase sediment amounts in freshwater environments[2].



Moulting occurs among Cambarus approximately 5-10 times during their first year, and 3-5 times during subsequent years. Cambarus remain relatively inactive during periods of moulting, as the shedding of chitin exoskeletons leaves them more vulnerable to predation and injury[3].


Cambarus typically mate in the early spring. Both Cambarus batonii and Cambarus robustus only mate once during their three year life span, with females of both carrying fewer eggs than those of the Orconectes genus[3].


Image Name
Cambarus aculabrum.jpg
Cambarus aculabrum
Cambarus georgiae (3086810921).jpg
Cambarus georgiea
Blue Crayfish - Cambarus monongalensis (165812772).jpg
Cambarus monogalensis


The genus Cambarus contains around 100 species, divided among 12 subgenera,[4][7] many of which are listed on the IUCN Red List:[8]

Subgenus Aviticambarus Hobbs, 1969
Subgenus Cambarus Erichson, 1846
Subgenus Depressicambarus Hobbs, 1969
Subgenus Erebicambarus Hobbs, 1969
Subgenus Exilicambarus Bouchard & Hobbs, 1976
Subgenus Glareocola Bouchard & Bouchard, 1995
Subgenus Hiaticambarus Hobbs, 1969
Subgenus Jugicambarus Hobbs, 1969
Subgenus Lacunicambarus Hobbs, 1969
Subgenus Puncticambarus Hobbs, 1969
Subgenus Tubericambarus Jezerinac, 1993
Subgenus Veticambarus Hobbs, 1969
  1. ^ Horton H. Hobbs, Jr. (1974). "A Checklist of the North and Middle American Crayfishes (Decapoda: Astacidae and Cambaridae)" (PDF). Smithsonian Contributions to Zoology. 166: 1–161. doi:10.5479/si.00810282.166.
  2. ^ a b c d e f Longshaw, Matt (2016). Biology and Ecology of Crayfish. New York: CRC Press. pp. 17–18. ISBN 9781498767323.
  3. ^ a b c d e f g Holdich, David M. (2002). Biology of Freshwater Crayfish. London: Blackwell Science. pp. 609–613. ISBN 0-632-05431-X.
  4. ^ a b James W. Fetzner, Jr. (January 14, 2008). "Genus Cambarus Erichson, 1846". Crayfish Taxon Browser. Carnegie Museum of Natural History. Retrieved March 9, 2010.
  5. ^ a b Cordeiro, J. (2014). "Cambarus diogenes". Encyclopedia of Life. Retrieved March 29, 2018.
  6. ^ a b c Buhay, J; et al. (February 2007). "Molecular taxonomy in the dark: Evolutionary history, phylogeography, and diversity of cave crayfish in the subgenus Aviticambarus, genus Cambarus". Molecular Phylogenetics and Evolution. 42: 435–448 – via ScienceDirect.CS1 maint: Explicit use of et al. (link)
  7. ^ "Cambarus". Integrated Taxonomic Information System.
  8. ^ "Search". IUCN Red List. IUCN. Retrieved October 7, 2010.
  9. ^ a b c Jennifer E. Buhay; Keith A. Crandall (2009). "Taxonomic revision of cave crayfish in the genus Cambarus subgenus Aviticambraus (Decapoda: Cambaridae) with descriptions of two new species, C. speleocoopi and C. laconensis, endemic to Alabama, U.S.A." (PDF). Journal of Crustacean Biology. 29 (1): 121–134. doi:10.1651/08-3089.1. Archived from the original (PDF) on 2011-07-19.
  10. ^ Roger F. Thoma; Zachary J. Loughman; James W. Fetzner, Jr. (2014). "Cambarus (Puncticambarus) callainus, a new species of crayfish (Decapoda: Cambaridae) from the Big Sandy River basin in Kentucky, Virginia, and West Virginia, USA" (PDF). Zootaxa. 3900 (4): 541–554. doi:10.11646/zootaxa.3900.4.5.