Disclaimer:

The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

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Common name: Western plains crayfish

Synonyms and Other Names: Orconectes causeyi (Jester, 1967), Causey's Crayfish, Conchas Crayfish. Faxonius causeyi underwent a reclassification in August 2017, changing the genus of non-cave dwelling Orconectes to Faxonius (Crandall and De Grave 2017).

Taxonomy: available through www.itis.gov

Identification: Faxonius causeyi has been described by Morehouse and Tobler (2013) and Pflieger (1996) as being a reddish-brown to olive brown color. The abdomen has two rows of black blotches running along it, which are especially prominent in young and recently molted individuals. The chelae (pinchers) have a bluish-green tint, with dark specks and yellow to off-white tubercles along the inner portion. The tips of the chelae are tipped with orange or orange-red. Faxonius causeyi is very similar in appearance to Faxonius virilis, but the outer tip of the mesial projection of the first swimmeret has a leaf-like thickening (Colorado Parks & Wildlife 2016).

Hobbs (1974) has commented that F. causeyi appears to be indistinguishable from Faxonius virilis (northern crayfish) and may not be a unique species. See F. virilis for more information.

Size: Adults rarely exceed 100 mm in total length (Morehouse and Tobler 2013)

Native Range: Faxonius causeyi is native to the Canadian River drainage in New Mexico, Oklahoma and Texas.It is also native to the Arkansas River drainage in Kansas, Oklahoma, and western edges of Missouri and Arkansas (Jester 1967; Dean 1969; Beasley and Branson 1971). There is no indication that the species is native in the lower Arkansas River in central Arkansas (Beasley and Branson 1971).

Alaska	Hawaii	Puerto Rico & Virgin Islands	Guam Saipan

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Ecology: Faxonius causeyi is a habitat generalist, and can be found in a range of substrates including rocks, sand and mud (Loring and Hill 1976). The species can be found in streams, ponds and reservoirs and is a tertiary burrower often tunneling under rocks embedded in the substrate (Dean 1969). Jester (1967) described the species as preferring cool headwater systems or the cool deep waters of reservoirs, however the species has been found in a range of temperatures (30-90° F; Dean 1969).

Form I males (sexually mature) have been collected from August through October, while form II males (molted post-reproduction males) and females have been collected year round. Juveniles were collected in New Mexico in July (Jester 1967).

Means of Introduction: Faxonius causeyi has been moved through bait buckets (Jester 1967) and stocked for biocontrol of aquatic plants (macrophytes) (Jester 1967; Dean 1969).

Status: Established in Arizona, Colorado, and New Mexico.

Impact of Introduction: Faxonius causeyi has the ability to reach high abundances (Jester 1976), and reduce the abundance of certain aquatic plants (macrophytes) which can influence habitat quality (Jester 1967; Dean 1969) and predator-prey fish interactions (Mullan 1975). 

Remarks: Both Oklahoma and New Mexico have recommended that F. causeyi be added to state lists of species of conservation concern (Morehouse and Tobler 2013; New Mexico SWAP 2016). 

References: (click for full references)

Beasley, C.W. and Branson, B.A. 1971. A partial biological survey of the Spring River drainage in Kansas, Oklahoma, and Missouri. Part III. The Crayfishes. Transactions of the Kansas Academy of Science 74:228-233.

Colorado Parks and Wildlife. 2016. Orconectus causeyi. Available at: http://cpw.state.co.us/learn/Lists/Wildlife%20Species/DispForm.aspx?ID=301 (Accessed: 6/8/17)

Crandall, K.A. and S. De Grave. 2017. An updated classification of the freshwater crayfishes (Decapoda: Astacidea) of the world, with a complete species list. Journal of Crustacean Biology 37(5):615-653. https://doi.org/10.1093/jcbiol/rux070.

Dean, J.L. 1969. Biology of the crayfish Orconectes causeyi and its use for control of aquatic weeds in trout lakes. Technical Papers of the Bureau of Sport Fisheries and Wildlife No. 24. U.S. Fish and Wildlife Service, Bureau of Sport Fisheries and Wildlife, Washington, DC.

Hobbs, H.H., Jr. 1974. A checklist of the North and middle American crayfishes (Decapoda: Astacidae and Cambaridae). Smithsonian Contributions to Zoology, Number 166.

Jester, D.B. 1967. A new crawfish of the genus Orconectes from New Mexico (Decapoda, Astacidae). The American Midland Naturalist 77(2):518-524.

Jester, D.B. 1976. Production of rough or commercial fishes in Elephant Butte Lake, New Mexico.Transactions of the American Fisheries Society 105(2): 222-231.

Loring, M.W., and L.G. Hill. 1976. Temperature selection and shelter utilization of the crayfish Orconectes causeyi. The Southwestern Naturalist 21(2):219-226.

Morehouse, R. L., and M. Tobler. 2013. Crayfishes (Decapoda: Cambaridae) of Oklahoma: identification, distributions, and natural history. Zootaxa 3717: 101-157.

Mullan, J.W. 1975. Fishery Management Program, Rocky Mountain Arsenal, Aurora, Colorado, Adams County. Special Project Report:22.

New Mexico Register. 2006. Commercial use of fishes. Available at: www.nmcpr.state.nm.us/nmregister.xuii/xvii02/19.31.9amend.pdf. (Accessed: 6/03/09).

Pflieger, W. L. 1996. The Crayfishes of Missouri. Missouri Department of Conservation, Jefferson City, Missouri.

State Wildlife Action Plan for New Mexico. 2016. Available at: www.wildlife.state.nm.us. (Accessed: 6/8/17)

Other Resources:
Natureserve

Colorado Parks and Wildlife

Encyclopedia of Life 

Author: Daniel, W.M.

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.