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.

Cambarellus shufeldtii
Cambarellus shufeldtii
(Cajun dwarf crayfish)
Native Transplant

Copyright Info
Cambarellus shufeldtii (Faxon, 1884)

Common name: Cajun dwarf crayfish

Taxonomy: available through www.itis.govITIS logo

Identification: Cambarellus shufeldtii are rust red to light brown with two distinct color patterns (spotted and striped) that occur in juveniles and adults of both genders. The spotted pattern is characterized by several rows of dark brown to steel-blue spots on the dorsolateral surfaces running from above the eyes to the last segment in the abdomen. The striped pattern is characterized by several dark brown, to steel-blue stripes alternating with opaque stripes of equal width running from above the eyes to the last segment in the abdomen (Penn 1942; Walls 2009, Taylor et al. 2015). There is no intermediate or blending of the two patterns (Penn 1942).

The defining morphological features of this species include a wide areola, a rostrum with a flattened dorsal surface and margins that terminate in small spines, the presence of hooks on the ischia of the second and third pair of walking legs, and gonopods of first form males with three straight terminal elements all in line with the main shaft. These features are well illustrated in Pflieger (1996), Walls (2009), and Taylor et al. (2015).

Size: Adults rarely exceed 28 mm total length (Taylor et al. 2015).

Native Range: Cambarellus shufeldtii is native to the Gulf Coastal Plain and margins of the Lower Mississippi alluvial basin (Pflieger 1996). This species occurs throughout Louisiana, north through the lower Mississippi mainstem and tributaries to Arkansas, Kentucky, Missouri, and Tennessee (Pflieger 1996; Walls 2009). The northernmost occurrence of the species was reported by Taylor and Tucker (2005) in Stump Lake, IL a backwater floodplain lake complex of the Illinois River. The native range extends east from the Mississippi alluvial basin along the Gulf Coast of Alabama to the Escambia River in Florida (Taylor and Tucker 2005; Pedraza-Lara et al. 2012). The western front of the native range includes the lower Red River in Louisiana and Texas and extends along the lower coastal plain into southeastern Texas to the Colorado and Brazos Rivers (Fitzpatrick 1983; Page 1985; Hobbs 1989; Taylor and Tucker 2005).

Though supported by some authors (Fitzpatrick 1983, Page 1985, Hobbs 1989, Pflieger 1996, Taylor and Tucker 2005), the eastern and western margins of the range described are contested by others, who suggest its native distribution is confined to the Mississippi alluvial plain (Penn 1942, Penn 1950, Walls 2009).

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

Nonindigenous Occurrences:

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Cambarellus shufeldtii are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
GA193719371Middle Chattahoochee-Lake Harding
KY197019701Upper Cumberland
MS201520152Noxubee; Tibbee

Table last updated 6/15/2024

† Populations may not be currently present.

Ecology: This species can be found in a wide range of habitats including: swamps, ditches, lakes, ponds, and sluggish streams (Penn 1950). Cambarellus shufeldtii is noted to prefer shallow (less than 15 inches), slow-moving, muddy habitats with numerous macrophytes (Penn 1950; Walls 2009). Peterson et al. (1996) described C. shufeldtii’s preference for oxbow side ponds on the Mississippi Gulf coast over adjacent channel habitats. These oxbows typically have lower turbidity, slower moving and warmer water, and support higher densities of aquatic vegetation compared to channel habits (Peterson et al. 1996).

Cambarellus shufeldtii is not an obligate burrower; however, it can endure periods of desiccation through taking refuge in underground “cells”. These cells are sealed from any surface connections and tend to be several inches deep. It is presumed that C. shufeldtii hollow out these cells as water recedes, and they are sealed into the sediments (Penn 1950; Pflieger 1996; Walls 2009).

Ovigerous females and form I males can be found almost anytime during the year (Black 1966). Despite the lack of seasonality in breeding, there are two main peaks in the year when reproductive activity is highest. The first is in late winter and early spring (December to March), and the second is in early summer (May to July) (Lowe 1961; Black 1966; Pflieger 1996). The young grow rapidly, maturing after about 2 months (Penn 1950). Female C. shufeldtii mature when they reach approximately 18 millimeters (mm) in total length (TL) (Lowe 1961). Although life expectancy of female C. shufeldtii is about one year, the average male may live 15-18 months (Black 1966). During its lifespan, the average female produces 2 broods of young (Lowe 1961; Pflieger 1996).

Means of Introduction: Most likely from bait bucket or aquarium releases, since the species is popular in both the aquarium and bait trade (Walls 2009; Faulkes 2015). Walls (2009) also suggested that Cambarellus shufeldtii has been introduced with hatchery and pond raised fishes.

Status: Kentucky Department of Fish and Wildlife Resources (2014) lists a Cambarellus shufeldtii occurrence from 1970 in Eastern Kentucky (Bell County), outside the native range. Penn (1942) noted that 18,000 C. shufeldtii were taken from Pearl River, Louisiana, and introduced in a private fish-culture project, the Peg Factory Lake, near Hamilton, Georgia, on March 15, 1937.

Walls (2009) lists occurrences in Texas and western Louisiana as introduced, but these are under further review.

Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range in the U.S. and associated territories. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.

Remarks: The range of C. shufeldtii is almost identical to that of C. puer, except that C. shufeldtii reaches further west into Texas (Hobbs 1989, Taylor and Schuster 2004). Despite this, they rarely occur together (Pflieger 1996). Penn and Fitzpatrick (1962) suggested that C. shufeldtii has increased its geographic range at the expense of the other dwarf crayfishes. This range expansion is suspected to occur due to the competitive exclusion of other species.

Penn (1942) described C. shufeldtii as an ideal forage food species to use in ponds or hatcheries. This is because it does not burrow deeply into embankments or levees, and it will not muddy the water by disturbing the sediment. Additionally, it has a protracted reproductive season, is not migratory, and its small size makes it a suitable food source for young fishes.

References: (click for full references)

Black, J.B. 1966. Cyclic male reproductive activities in the dwarf crawfishes Cambarellus shufeldtii (Faxon) and Cambarellus puer Hobbs. Transactions of the American Microscopical Society 85(2):214-232.

Faulkes, Z. 2015. Marmorkrebs (Procambarus fallax f. virginalis) are the most popular crayfish in the North American pet trade. Knowledge and Management of Aquatic Ecosystems 416 (20).

Fitzpatrick, J.F., Jr. 1983. A revision of the dwarf crawfishes (Cambaridae, Cambarellinae). Journal of Crustacean Biology 3(2):266-277. https://www.jstor.org/stable/1548262.

Hobbs, H.H., Jr. 1989. An illustrated checklist of the American crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions to Zoology 480:1-236.

Kentucky Department of Fish and Wildlife Resources. 2014. Cambarellus shufeldtii. http://app.fw.ky.gov/speciesinfo/speciesListCounty.asp?strScientificName=Cambarellus+shufeldtii&strGroup=14 (Accessed on 02/20/2018)

Lowe, M.E. 1961. The female reproductive cycle of the crayfish Cambarellus shufeldtii: the influence of environmental factors. Tulane Studies in Zoology and Botany 8:157-176.

Page, L.M. 1985. The crayfishes and shrimps (Decapoda) of Illinois. Volume 33. State of Illinois Department of Energy and Natural Resources, Champaign, IL. https://www.ideals.illinois.edu/bitstream/handle/2142/44052/Bulletin33%284%29.pdf?sequence=2&isAllowed=y.

Pedraza-Lara, C., I. Doadrio, J.W. Breinholt, and K.A. Crandall. 2012. Phylogeny and evolutionary patterns in the dwarf crayfish subfamily Decapoda: Cambarellinae). PLoS ONE 7(11):e48233. https://doi.org/10.1371/journal.pone.0048233.

Penn, Jr., G.H. 1942. Observations on the biology of the dwarf crawfish, Cambarellus shufeldtii (Faxon). American Midland Naturalist 28(3):644-647.

Penn, Jr., G.H. 1950. The Genus Cambarellus in Louisiana (Decapoda, Astacidae). American Midland Naturalist 44(2):421-426.

Penn, Jr., G.H., and J.F. Fitzpatrick. 1963. Interspecific competition between two sympatric species of dwarf crawfishes. Ecology 44(4):793-797. https://doi.org/10.2307/1933033.

Peterson, M.S., Fitzpatrick, J.F., & S.J. VanderKooy. 1996. Distribution and habitat use by dwarf crayfishes (Decapoda: Cambaridae: Cambarellus). Wetlands 16(4):594-598.

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

Taylor, C.A., and G.A. Schuster. 2004. The crayfishes of Kentucky. Illinois Natural History Survey, Champaign, IL.

Taylor, C. A., and Tucker, J. K. 2005. New distributional records for Illinois crayfishes (Decapoda: Cambaridae) with comments on the continued spread of non-native species. Transactions of the Illinois Academy of Science 98:75-80.

Taylor, C.A., G.A. Schuster, and D.B. Wylie. 2015. Field guide to crayfishes of the Midwest. Illinois Natural History Survey, Champaign, IL.

Walls, J.G. 2009. Crawfishes of Louisiana. Louisiana State University Press, Baton Rouge, LA.

Author: Procopio, J., and Daniel, W.M.

Revision Date: 4/15/2019

Peer Review Date: 4/15/2019

Citation Information:
Procopio, J., and Daniel, W.M., 2024, Cambarellus shufeldtii (Faxon, 1884): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=204, Revision Date: 4/15/2019, Peer Review Date: 4/15/2019, Access Date: 6/15/2024

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.


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Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/15/2024].

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