Common name: Pilose Crayfish
available through www.itis.gov
Pacifastacus gambelli have pigmented eyes, a rostrum with margins, and at least 3 lateral marginal spines. Other diagnostic characteristics include postorbital ridges without posterior spines/ tubercles and a palm with a studded dorsal surface. These studs include minute tubercles and 2 longitudinal clusters of setae (Hobbs 1972).
Size: Average size is 39.7mm for females and 28.9mm for males (Kawai 2012).
Native Range: This species is was initially thought to have been native to Idaho, Wyoming, Montana, Oregon, Washington, Nevada and Utah but were mis-identified as Pacifastacus connectens (Hobbs 1972). Thus, the pilose crayfish were only native to Idaho, Montana, Nevada, Wyoming and Utah. Pilose crayfish are specifically found in the Snake River and it's tributaries throughout Idaho, Nevada, Utah and Wyoming (Miller 1960). They are also abundant in the Great Salt Lake tributaries such as the Bear and Weber rivers in Utah and Wyoming (Johnson 1986). This is the only extant member of its genus east of the Continental Divide.
Interactive maps: Point Distribution Maps
Puerto Rico &
Possible introduction in California, location unknown (Hobbs 1989).
Ecology: Pilose crayfish are found in lentic and lotic systems. Studies have shown that they are intolerable of warm waters, possibly because of the warm water fish species that predate on crayfish (Johnson 1986). This species breeds in the springtime, and have a small home range of 50 meters (Wyoming Game and Fish Department 2002).
Means of Introduction: Possible bait bucket introduction.
Impact of Introduction: Unknown.
References: (click for full references)
Hobbs, H. H., Jr. 1972. The subgenera of the crayfish genus Procambarus
(Decapoda: Astacidae). Smithsonian Contributions to Zoology 117:1-22.
Hobbs, H. H., Jr. 1989. An illustrated checklist of the American crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions to Zoology 480:1-236.
Johnson, J.E. 1986. Inventory of Utah crayfish with notes on current distribution. The Great Basin Naturalist 46(4):625-631.
Kawai, T. 2012. Re-description of Pacifastacus gambelii (Decapoda: Astacidae). Crustacean research, special number 7(1): 59-68.
Miller, G.C. 1960. The taxonomy and certain biological aspects of the crayfish of Oregon and Washington. Masters Thesis, Oregon State College.
Wyoming Game and Fish Department. 2002. Mollusks and Crustaceans. Available from: http://gf.state.wy.us/wildlife/CompConvStrategy/Species/MollusksCrustaceans/PDFS/Crayfish.pdf [Accessed 8/8/2017].
Revision Date: 8/8/2017
Hosabettu, Maya, 2018, Pacifastacus gambelii (Girard, 1852): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=199, Revision Date: 8/8/2017, Access Date: 1/16/2018
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.