Conservation, Biology, and Natural History of Crayfishes from the Southern US 2010 Southeastern Naturalist 9(Special Issue 3):127–138 History, Status, and Conservation of Georgia Crayfishes Christopher E. Skelton* Abstract - Georgia has historically had one of the best-known crayfish faunas in the United States, mainly due to the work of Dr. Horton H. Hobbs, Jr. In The Crayfishes of Georgia, published in 1981, Hobbs recognized 66 species and subspecies from the state, including 1 species that he hypothesized to be extinct, Procambarus (Ortmannicus) angustatus (Sandhills Crayfish). Herein I document 68 extant native species and subspecies, 1 extinct species, and 3 non-native species. Of the 68 extant native taxa, 17 (25%) are endemic to Georgia. A recent evaluation of the conservation status of United States crayfishes suggests that 6 Georgia species are endangered, 10 threatened, 7 vulnerable, and 1 extinct. The state of Georgia currently lists 7 species as endangered, 10 threatened, and 3 rare and has instituted new rules to protect crayfishes from export for the pet trade, while still permitting collection of some species for bait. Taxonomic studies continue on Georgia crayfishes, with at least 2 forms being examined as probable new species. Of the 3 non-native species now present in Georgia, Orconectes (Buannulifictus) palmeri creolanus (Creole Painted Crayfish) appears to be expanding its range, while the status of Procambarus (Scapulicambarus) clarkii (Red Swamp Crawfish) remains poorly understood. In addition to the presence of non-native taxa, threats to native Georgia crayfishes include persistent drought and land development associated with rapid human population growth. Introduction Georgia has historically had one of the best-known crayfish faunas in the United States. This can be attributed almost solely to the work of Dr. Horton H. Hobbs, Jr. In The Crayfishes of Georgia, Hobbs (1981) presented detailed accounts of 66 species and subspecies, reviewed the history of crayfish study in the state, and presented hypotheses on the biogeography and phylogenetic relationships of the fauna. In this paper, I provide an overview of the crayfish fauna of Georgia, including a brief history of crayfish study in the state and the status of the fauna as currently recognized. Persons seeking more detail concerning the history, origin, relationships, and distribution of Georgia crayfishes should refer to Hobbs (1981). The first descriptions of crayfishes from Georgia were published by John LeConte (1856). He described 8 new species; however, only 5 of them remain valid: Cambarus (Depressicambarus) latimanus (LeConte) (Variable Crayfish), Procambarus (Hagenides) advena (LeConte) (Vidalia Crayfish), P. (Ortmannicus) angustatus (LeConte) (Sandhills Crayfish), P. (Pennides) spiculifer (LeConte) (White Tubercled Crayfish), and P. (Scapulicambarus) troglodytes (LeConte) (Eastern Red Swamp Crawfish). Fourteen years later, Hagen (1870) described C. (Puncticambarus) *Department of Biological and Environmental Sciences, Georgia College and State University, Milledgeville, GA 31061; chris.skelton@gcsu.edu. 128 Southeastern Naturalist Vol. 9, Special Issue 3 extraneus Hagen (Chickamauga Crayfish) and P. (O.) lecontei (Hagen) (Mobile Crayfish) from Georgia. The inclusion of P. lecontei as part of the Georgia fauna was in error, however, as it is known only from Alabama and Mississippi (Hobbs 1989). Bundy (1877), a physician from Michigan, described Orconectes (Procericambarus) spinosus (Bundy) (Coosa River Spiny Crayfish) from the Rome area, and Faxon (1884) provided descriptions of two new Georgia species, P. (O.) pubescens (Faxon) (Brushnose Crayfish) and C. jordani (Faxon). The latter has since been synonymized with C. latimanus (Bouchard 1978). Hobbs acquired his first crayfish specimens from Georgia in 1936 and published his first descriptions of crayfishes from the state in 1947 (Hobbs 1947). After those first descriptions, he published more than 10 papers on Georgia crayfishes, culminating in his classic work, The Crayfishes of Georgia (Hobbs 1981). Forty-three of the 68 native species and subspecies that are known from the state were described by Dr. Hobbs, including 19 new forms listed in The Crayfishes of Georgia. Subsequent of The Crayfishes of Georgia, I am aware of only 3 published papers have been published relating specifically to Georgia crayfishes. Cooper and Skelton (2003) described a new Depressicambarus from southwestern Georgia, C. (D.) doughertyensis Cooper and Skelton (Dougherty Burrowing Crayfish), and Stanton (2003) reported the first occurrence of P. (O.) verrucosus Hobbs (Grainy Crayfish) from the state. Dennard et al. (2009) report on the life history and ecology of a Tallapoosa River endemic, C. (D.) halli Hobbs (Slackwater Crayfish). Unpublished work by Skelton et al. (2002) and Stanton (2006) contributed to the knowledge of Georgia crayfishes. Skelton et al. (2002) assessed the conservation status of 4 rare burrowing species: C. (D.) cymatilis Hobbs (Conasauga Blue Burrower), C. (D.) harti Hobbs (Piedmont Blue Burrower), C. (D.) truncatus Hobbs (Oconee Burrowing Crayfish), and Distocambarus devexus (Hobbs) (Broad River Burrowing Crayfish). Despite finding new occurrences of each of these primary burrowing species, all 4 have very restricted ranges and are listed as either threatened or endangered by the state of Georgia. Stanton’s (2006) study evaluated the status of one primary burrower, C. harti, and 5 stream species—C. (Cambarus) howardi Hobbs and Hall (Chattahoochee Crayfish), P. (O.) acutissimus (Girard) (Sharpnose Crayfish), P. (Pe.) gibbus Hobbs (Muckalee Crayfish), P. verrucosus and P. (Pe.) versutus (Hagen) (Sly Crayfish)—from the Chattahoochee and Flint river systems. The 4 Procambarus species have restricted ranges, but appear to be stable at this time. The distribution of C. howardi essentially straddles the Atlanta metropolitan area, and Stanton (2006) was unable to find it at several historical localities. Physiography of Georgia Georgia contains portions of 5 major physiographic provinces, of which the Piedmont and Coastal Plain dominate the state (Fig. 1). A small piece of the Appalachian Plateau occupies the northwestern corner of the state. 2010 C.E. Skelton 129 Major features in this area are Sand, Lookout, and Pigeon mountains. Streams that drain this region enter either the Tennessee River (Cole City, Lookout, Chattanooga, and West Chickamauga creeks) or flow south to the Mobile Basin (Chattooga and Little rivers). This region is home to only 8 species of crayfishes. Directly east and south of the Appalachian Plateau region is the Ridge and Valley Province. This province contains a highly diverse aquatic fauna (Boschung and Mayden 2004, Etnier and Starnes 1993, Williams et al. 2008) and has the highest ratio of crayfish species to land area of any region of Georgia. The majority of the Ridge and Valley Province is drained by the Coosa River system which is the northeastern portion of the Mobile Basin. In Georgia, major Coosa River tributaries are the Chattooga, Conasauga, Coosawattee, and the Etowah river systems. Within Georgia, the Coosa River proper is comprised of only a short reach (ca. 30 river kilometers) Figure 1. Major drainage systems and physiography of Georgia: 1. Tennessee, 2. Conasauga, 3. Hiwassee, 4. Little Tennessee, 5. Chattooga, 6. Coosa, 7. Coosawattee, 8. Tallapoosa, 9. Etowah, 10. Broad, 11. Savannah, 12. Chattahoochee, 13. Flint, 14. Ocmulgee, 15. Oconee, 16. Ohoopee, 17. Ogeechee, 18. Ochlockonee, 19. Aucilla, 20. Suwannee, 21. St. Mary’s, 22. Satilla, 23. Altamaha, 24. Canoochee, and 25. Newport. 130 Southeastern Naturalist Vol. 9, Special Issue 3 stretching from Rome to the Georgia–Alabama border. This river system was historically one the most diverse in North America, but this diversity has declined as a result of human activities including reservoir construction and poor land-use practices. The other major drainage in this province is the South Chickamauga Creek system, which empties into the Tennessee River at Chattanooga. Twenty species and 1 subpecies of crayfishes are known from the Ridge and Valley Province. The Blue Ridge Province covers the northeastern corner of the state and is bounded to the west by the Ridge and Valley and to the south by the Piedmont. The headwaters of several large drainage systems lie in the Blue Ridge including portions of the Savannah, Coosa, and Chattahoochee rivers. This province is slightly smaller than the Ridge and Valley and correspondingly has fewer crayfishes, with 14 species found there. The reduced richness can be attributed in part to the abundance of cold, high-gradient streams in the province. The Piedmont Province spans the entire width of Georgia and is bounded by the Ridge and Valley and Blue Ridge provinces in the north and Coastal Plain Province to the south. The Fall Line forms the boundary between the Piedmont and Coastal Plain. This narrow, complex feature marks an abrupt drop in elevation where crystalline rocks of the Piedmont give way to softer sediments in the Coastal Plain (Clark and Zisa 1976). Most of the large river systems in the state flow through the Piedmont for a least a part of their length. Generally speaking, the Piedmont is not recognized as having an exceptionally diverse aquatic fauna. For example, 23 native crayfish species are known from this province, which is comparable to the 21 taxa known from the Ridge and Valley Province. The Ridge and Valley however, is drained primarily by a single river system (as opposed to 7 draining the Piedmont) and is only about one-fourth the size of the Piedmont. This trend of reduced aquatic biodiversity is seen in other aquatic groups such as fishes and freshwater mussels. The Coastal Plain Province encompasses about one-half the land area of Georgia. Streams there are typically sluggish and meandering with broad floodplains. Except for the Coosa, all of the major river systems in Georgia pass through the Coastal Plain. The Suwannee, Ochlockonee, Satilla, St. Mary’s, and Ohoopee rivers, and the Altamaha River proper are restricted to the Coastal Plain. Thirty-five crayfish species and 1 subspecies are found in this province. Crayfish Fauna Current counts indicate Georgia has 68 extant native species and subspecies and 3 non-native species (Appendix I). The bulk of the fauna is represented by Cambarus (33 species, 1 subspecies) and Procambarus (28 species, 1 subspecies) species, with 4 Orconectes and 1 representative each of the genera Distocambarus, Fallicambarus, and Faxonella. Since the publication of Hobbs (1981), 6 additional species of crayfishes have been added to the Georgia fauna including C. doughertyensis, O. p. creolanus, P. (O.) chacei Hobbs (Cedar Creek Crayfish), P. (O.) hayi (Faxon) (Straightedge Crayfish), P. (S.) clarkii (Girard) (Red Swamp Crayfish), and P. verrucosus. Cambarus doughertyensis was described from a single 2010 C.E. Skelton 131 location in the Flint River system (Cooper and Skelton 2003) and is the only taxon since Hobbs (1981) that represents a new species. Orconectes p. creolanus, P. clarkii, and P. hayi are not native to Georgia and are reported here for the first time as occurring in the state (see the “introduced species” section for more discussion). Hobbs (1981) synonymized P. chacei with P. (O.) enoplosternum Hobbs (Black Mottled Crayfish), but later reversed his decision upon examination of additional material (Hobbs 1989). Because of this confusion, the distribution of these species as presented in Appendix I should be considered tentative. Procambarus verrucosus reaches the eastern limit of its range in western Georgia and is known from only a few sites in the Columbus area (Stanton 2006). Hobbs (1981) included P. angustatus as part of the Georgia fauna, although he suggested that it might be extinct. I have chosen to exclude this species from the counts below because the only specimen ever collected was the type specimen, which is now lost. Further, the type locality listed by LeConte (1856) was too vague for Hobbs to determine the drainage from which it was collected, and it now seems doubtful that additional specimens will be found. Hobbs (1981) also included C. (P.) chaugaensis Prins and Hobbs (Chauga Crayfish) as occurring in Georgia based on a single collection of 10 specimens from Gold Mine Creek (Savannah River drainage) in Rabun County. Additional collections in Gold Mine Creek and surrounding areas by Hobbs (1981) and I failed to produce more individuals of this species. I consider C. chaugaensis tentative on the state list and do not include it in the species counts in this paper. Hobbs (1981) listed 2 species that could possibly be found in Georgia because of the proximity of their respective ranges, C. (Aviticambarus) hamulatus (Cope) (Prickly Cave Crayfish) and P. (O.) leonensis Hobbs (Blacknose Crayfish). Cambarus hamulatus is an obligate troglobitic (cavedwelling) species known from karst regions in northeastern Alabama and southeastern Tennessee (Buhay et al. 2007). Since the range of a troglobitic fish Typhlichthys subterraneus Girard (Southern Cavefish) includes northwestern Georgia, northeastern Alabama, and southeastern Tennessee (Boschung and Mayden 2004), it seems plausible that C. (A.) hamulatus could also occur in Georgia. However, based on extensive fieldwork conducted for cave crayfishes in Alabama and Tennessee, and numerous expeditions by the caving community in northwestern Georgia, it now appears doubtful that C. hamulatus occurs in the state (J. Buhay, University of South Carolina, Columbia, SC, pers. comm.). Procambarus leonensis occurs close to the Georgia border in the Aucilla and Ochlockonee river systems in northern Florida (Hobbs 1981). I have surveyed both rivers near the border, but as yet have failed to find P. leonensis. Crayfish Distributions Appendix I lists all of the Georgia crayfish taxa by river system and physiographic province. In terms of species numbers, the Altamaha River system is the richest with 23 native species, and is followed by the Savannah with 19 and the Coosa with 18. 132 Southeastern Naturalist Vol. 9, Special Issue 3 Of the extant Georgia forms, 17 are endemic to the state and 7 of those are endemic to a single river system. The latter count is somewhat arbitrary as it is based on the rivers I included in the appendix. For example, it could be argued that C. (D.) strigosus Hobbs (Lean Crayfish) is endemic to a single river system (Savannah), but I did not include it as such because it is found in two large Savannah River tributaries. One of those is the Broad, which I considered large enough to appear in the appendix. In terms of distribution by physiographic province, the fauna is more or less divided into two parts. Above the Fall Line, the genus Cambarus dominates the fauna, with all but a handful of the species occurring there. The only Cambarus that occur exclusively in the Coastal Plain are C. doughertyensis, C. truncatus, C. (J.) cryptodytes Hobbs (Dougherty Plain Cave Crayfish), and possibly C. (D.) reflexus Hobbs (Pine Savannah Crayfish). Cambarus latimanus occurs primarily in the Piedmont province, but there are several populations in the Coastal Plain. Cambarus (D.) striatus Hay (Ambiguous Crayfish) can also be found in the Coastal Plain, but its range is concentrated in the Ridge and Valley Province. The range of C. (L.) diogenes Girard (Devil Crawfish) is essentially the reverse of the latter two, with most populations occurring in the Coastal Plain and a few occurring in the Piedmont. The genus Procambarus comprises the majority of the species found in the Coastal Plain. Of the 29 taxa known from Georgia, only P. (O.) lophotus Hobbs and Walton (Mane Crayfish) occurs exclusively outside of the Coastal Plain and is apparently restricted to the Ridge and Valley Province. Procambarus spiculifer is the most widely distributed crayfish in Georgia, and roughly half of its populations occur above the Fall Line and half below. Another member of the subgenus, P. (Pe.) raneyi Hobbs (Disjunct Crayfish) has populations above and below the Fall Line, but is most abundant the Piedmont Province. Procambarus pubescens is the only other member of the genus with a large portion of its populations occurring above the Fall Line (ca. one-third). The remaining genera are scattered in different portions of the state. Distocamabarus devexus (Broad River Burrowing Crayfish) is found only in the Piedmont Province in the Broad River system and nearby tributaries to the Savannah River. Except for a possible introduced population in the Piedmont, Faxonella clypeata (Hay) (Ditch Fencing Crayfish) is restricted to the Coastal Plain. Fallicambarus (Creaserinus) fodiens (Cottle) (Digger Crayfish) and O. palmeri creolanus are also found only in the Coastal Plain. The three remaining Orconectes (erichsonianus, forceps, and spinosus) are found almost exclusively in the Ridge and Valley Province, with only O. (Crockerinus) erichsonianus (Faxon) (Reticulate Crayfish) venturing slightly into the Appalachian Plateau Province. Threats and Conservation Generally speaking, the crayfish fauna in Georgia appears to be stable. However, Georgia is one of the fastest growing states in the country, and the 28-county Atlanta metropolitan area contains more than half of the 2010 C.E. Skelton 133 human population of the state (>5 million). This large population center is stretching limited water resources and drastically altering stream flows and riparian areas, thereby severely degrading many streams. An additional statewide risk fostered by continuing drought is the threat of increased reservoir development. A recent evaluation of the conservation status of United States crayfishes suggests that 6 Georgia taxa are endangered, 9 threatened, 7 vulnerable, 1 extinct, and 48 currently stable (Taylor et al. 2007). This publication, along with Taylor et al.’s (1996) initial paper describing the conservation status of US crayfishes has increased the visibility of this interesting and ecologically important fauna. These papers were in large part the catalyst for the state of Georgia to evaluate the status of the states’s crayfish fauna. Thus, a recent revision of the Georgia Protected Species list included 20 crayfishes. Of these 20, 7 species are listed as endangered, 10 threatened, and 3 rare (Table 1). Most of these species have restricted ranges and are also considered globally rare. In addition to adding species to the protected animals list, new rules were put in place to protect crayfishes from export for the pet trade and to restrict the collection of burrowing species. Unfortunately, the use of crayfishes as bait is still allowed. It has been well documented that the introduction of non-native invasive crayfishes is one of the greatest threats facing native species, and the use of crayfishes as bait is a primary vector for those introductions (Lodge et al. 2000). Table 1. Conservation status of protected crayfish species in Georgia indicating rankings by the American Fisheries Society (AFS), NatureServe (Heritage Rank), and the state of Georgia. E = endangered, T = threatened, SC = special concern, V = vulnerable, and CS = currently stable. AFS Heritage Species Common name 1996 2007 rank GA Cambarus (H.) coosawattaeA Coosawattee Crayfish E E G1 E Cambarus (J.) cryptodytes Dougherty Plain Cave Crayfish T T G2G3 T Cambarus (D.) cymatilis Conasauga Blue Burrower E E G1 E Cambarus (D.) doughertyensisA Dougherty Burrowing Crayfish NAB E G1 E Cambarus (D.) englishi Tallapoosa Crayfish SC V G3 R Cambarus (P.) extraneus Chickamauga Crayfish T T G2 T Cambarus (H.) fasciatusA Etowah Crayfish T T G3 T Cambarus (P.) georgiae Little Tennessee Crayfish E V G2 E Cambarus (D.) hartiA Piedmont Blue Burrower E E G1 E Cambarus (C.) howardi Chattahoochee Crayfish SC CS G3 T Cambarus (P.) parrishi Hiwassee Headwater Crayfish E E G2 E Cambarus (P.) scotti Chattooga River Crayfish T T G3 T Cambarus (H.) speciosusA Beautiful Crayfish E E G2 E Cambarus (D.) strigosusA Lean Crayfish T T G2 T Cambarus (D.) truncatusA Oconee Burrowing Crayfish E T G2 T Cambarus (J.) unestami Blackbarred Crayfish T T G2 T Distocambarus (D.) devexusA Broad River Burrowing Crayfish E T G1 T Procambarus (Pe.) gibbusA Muckalee Crayfish SC T G3 T Procambarus (O.) verrucosus Grainy Crayfish CS CS G4 R Procambarus (Pe.) versutus Sly Crayfish CS CS G5 R AEndemic to Georgia. BSpecies not described until 2003. 134 Southeastern Naturalist Vol. 9, Special Issue 3 Taylor et al. (2007) considered small range size to be a major threat to crayfishes and it certainly applies to several Georgia species. As mentioned above, 7 Georgia species are found in only a single river system, and some of these are known from fewer than 10 locations. Such small ranges can be severely reduced by the construction of a strip mall, or completely eliminated by a reservoir. Introduced species. There are currently 3 known introduced crayfish species established within the state. Procambarus clarkii has long been known from a single stream in downtown Athens, but it is not known if they have spread into the nearby Oconee River or its tributaries. In a recent survey in Gwinnett County (September 2007), a single specimen of P. clarkii was found in a highly disturbed urban stream. In July 2008, several individuals were collected in an urban stream in the Etowah River system. The recent finding in the Etowah system is disturbing because of potential negative effects to the endemic C. (H.) fasciatus Hobbs (Etowah Crayfish). Procambarus clarkii has been introduced so widely (Huner and Barr 1991) that it will likely turn up in additional locations within the state. In October 1999, a form I male Orconectes was collected from the Flint River about 18 km south of Albany. The animal was tentatively identified as O. palmeri and later verified as O. palmeri creolanus by John Cooper (NC Museum of Natural Sciences, Raleigh, NC, pers. comm.). That same year, George Stanton (Columbus State University, Columbus, GA, pers. comm.) found an additional individual of the species in the Flint River at the mouth of Muckalee Creek in Albany. A current study on the distribution and population dynamics of O. palmeri creolanus indicates that the species inhabits approximately 120 river kilometers of the Flint River from just north of Bainbridge to about 12 kilometers north of Albany. Preliminary data suggests O. palmeri creolanus may be displacing the native P. spiculifer in the upper part of this reach (Lindsay Sargent, Joseph F. Jones Ecological Research Center, Newton, GA, pers. comm.). Although P. spiculifer is widespread and common throughout the state, another Pennides species (P. gibbus) is nearly endemic to a large Flint River tributary, Muckalee Creek. Thus far, O. palmeri creolanus has not been collected or seen in any Flint River tributary; however, if O. p. creolanus are able to spread into Muckalee Creek, the continued existence of P. gibbus will be uncertain. In April 2009, a form I male Procambarus was dug from a simple burrow in a roadside ditch in Newton County (Oconee River drainage). It was subsequently collected from two nearby streams and tentatively identified as P. (O.) hayi. Recent examination of P. hayi specimens from Mississippi (part of P. hayi’s native range) confirms this identifiction. It is not clear how widespread this species is in Georgia, nor how it was introduced. Conclusion Much remains to be learned about the crayfishes of Georgia. The state is fairly well known in terms of its faunal components and distribution of that fauna; however, little is known about the life history of most species 2010 C.E. Skelton 135 in the state. Because of the difficulty collecting burrowing species, there is additional distributional work to be conducted regarding the nearly 20 species of primary burrowers that occur in Georgia. Finally, I suspect the use of molecular techniques to elucidate boundaries between species will likely result in the discovery of cryptic species. Threats to Georgia crayfishes stem primarily from the high degree of endemism exhibited by the group. Seventeen species are found nowhere else in the world, and several species are known from only a handful of locations. These small ranges subject the various species to a higher likelihood of substantial range reduction from small perturbations. On the bright side, this group of potentially vulnerable crayfish species is receiving increased positive attention from state agencies and the public. Additionally, it seems that more researchers are interested in studying crayfishes, which will hopefully provide the knowledge needed to support the increased conservation of this interesting and diverse fauna. Acknowledgments I thank S. Adams for providing comparative material that facilitated crayfish identifications. Many thanks fot to T. Waters, S. Welsh, and S. Loughman for organizing the 2007 Southern Division AFS crayfish symposium and the resulting proceedings. Zac Loughman and one anonymous reviewer provided helpful comments that improved this manuscript. Funding to defray publication costs was provided in part by the US Geological Society, West Virginia Cooperative Fish and Wildlife Research Unit. Special thanks go to S. Welsh for many manuscript edits and for organizing partial funding for publication costs. Literature Cited Boschung, H.T., Jr., and R.L. Mayden. 2004. Fishes of Alabama. Smithsonian Institution Press. Washington, DC. 736 pp. Bouchard, R.W. 1978. Taxonomy, ecology, and phylogeny of the subgenus Depressicambarus, with the description of a new species from Florida and redescriptions of Cambarus graysoni, Cambarus latimanus, and Cambarus striatus (Decapoda: Cambaridae). Bulletin of the Alabama Museum of Natural History 3:27–60. Buhay, J.E., G. Moni, N. Mann, and K.A. Crandall. 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. Bundy, W.F. 1877. On the Cambari of northern Indiana. Proceedings of the Academy of the Natural Sciences of Philadelphia 29:171–174. Clark, W.Z., Jr., and A.C. Zisa. 1976. Physiographic map of Georgia. Geologic and Water Resources Division, Department of Natural Resources, Atlanta, GA. Cooper, J.E., and C.E. Skelton. 2003. A new burrowing crayfish of the genus Cambarus Erichson, 1846 (Decapoda: Cambaridae) from the lower Flint River basin in the Dougherty Plain of Georgia, with notes on C. (D.) harti Hobbs, 1981. Proceedings of the Biological Society of Washington 116(3):827–838. Dennard. S., J.T. Peterson, and E.S. Hawthorne. 2009. Life history and ecology of Cambarus halli (Hobbs). Southeastern Naturalist 8:479–494. 136 Southeastern Naturalist Vol. 9, Special Issue 3 Etnier, D.A., and W.C. Starnes. 1993. The Fishes of Tennessee. University of Tennessee Press, Knoxville, TN. 681 pp. Faxon, W. 1884. Descriptions of new species of Cambarus; to which is added a synonymical list of the known species of Cambarus and Astacus. Proceedings of the American Academy of Arts and Science 20:107–158. Hagen, H.A. 1870. Monograph of the North American Astacidae. Illustrated Catalogue of the Museum of Comparative Zoology at Harvard College 3:109 pp. Hobbs, H.H., Jr. 1947. Two new crayfishes of the genus Procambarus from Georgia, with notes on Procambarus pubescens (Faxon) (Decapoda, Astacidae). Quarterly Journal of the Florida Academy of Sciences 9(1):1–18. Hobbs, H.H., Jr. 1981. The crayfishes of Georgia. Smithsonian Contributions to Zoology 318:1–549. Hobbs, H.H., Jr. 1989. An illustrated checklist of the American crayfishes (Decapoda: Astacidae, Cambaridae, and Parastacidae). Smithsonian Contributions to Zoology 480:1–236. Huner, J.V., and J.E. Barr. 1991. Red Swamp Crawfish: Biology and Exploitation, 3rd Edition. Louisiana Seagrant College Program, Louisiana State University, Baton Rouge, LA. LeConte, J. 1856. Descriptions of new species of Astacus from Georgia. Proceedings of the Academy of Natural Sciences of Philadelphia 7:400–402. Lodge, D.M., C.A. Taylor, D.M. Holdich, and J. Skurdal. 2000. Nonindigenous crayfishes threaten North American freshwater biodiversity: Lesson from Europe. Fisheries 25(8):7–20. Skelton, C.E., S.E. Cammack, and E.E. VanDeGenachte. 2002. Surveys of rare burrowing crayfishes. Final Report, Georgia Department of Natural Resources, Georgia Natural Heritage Program, Social Circle, GA. 13 pp. Stanton, G.E. 2003. First record of the crayfish Procambarus (Ortmannicus) verrucosus Hobbs in Georgia. Southeastern Naturalist 2(4):615–618. Stanton, G.E. 2006. Evaluation of conservation status of six West Georgia, Chattahoochee– Flint River crayfish species. Final Report, Georgia Department of Natural Resources, Georgia Natural Heritage Program, Social Circle, GA. 60 pp. Taylor, C.A., M.L. Warren, Jr., J.F. Fitzpatrick, Jr., H.H. Hobbs III, R.F. Jezerinac, W.L. Pflieger, and H.W. Robison. 1996. Conservation status of crayfishes of the United States and Canada. Fisheries 21(4):25–38. Taylor, C.A., G.A. Schuster, J.E. Cooper, R.J. DiStefano, A.G. Eversole, P. Hamr, H.H. Hobbs III, H.W. Robison, C.E. Skelton, and R.F. Thoma. 2007. A reassessment of the conservation status of crayfishes of the United States and Canada after 10+ years of increased awareness. Fisheries 32(8):372–389. Williams, J.D., A.E. Bogan, and J.T. Garner. 2008. Freshwater Mussels of Alabama and the Mobile Basin in Georgia, Mississippi, and Tennessee. University of Alabama Press, Tuscaloosa, AL. 960 pp. 2010 C.E. Skelton 137 Appendix I. Georgia crayfish taxa by drainage system and physiographic province. Numbers refer to Fig. 1. A = Appalachian Plateau; B = Blue Ridge; C = Coastal Plain; P = Piedmont; R = Ridge and Valley. Superscripts: Aendemic, Bintroduced, Cprobably extinct, and Dprobably introduced. Cambarus (Tubericambarus) acanthura Hobbs (Thornytail Crayfish): 1R, 2R, 3B, 5R, 6R, 7PR, 8P, 9R, 12P, 14P C. (Jugicambarus) asperimanus Faxon (Mitten Crayfish): 11BP C. (Cambarus) bartonii bartonii (Fabricius) (Common Crayfish): 2BR, 3B, 10P, 11BP, 12BP, 15P C. (C.) b. cavatus Hay (Appalachian Brook Crayfish): 1AR C. (Puncticambarus) chaugaensis Prins and Hobbs (Chauga Crayfish):11B? C. (J.) conasaugaensis Hobbs and Hobbs (Mountain Crayfish): 2BR, 7BPR, 9BP C. (P.) coosae Hobbs (Coosa Crayfish): 2BR, 6R, 7R, 9PR C. (Hiaticambarus) coosawattaeA Hobbs (Coosawattee Crayfish): 7BR C. (J.) cryptodytes Hobbs (Dougherty Plain Cave Crayfish): 13C C. (Depressicambarus) cymatilis Hobbs (Conasauga Blue Burrower): 2R C. (Lacunicambarus) diogenes Girard (Devil Crawfish): 11C, 12CP, 13CP, 14P C. (J.) distans Rhoades (Boxclaw Crayfish): 1A C. (D.) doughertyensisA Cooper and Skelton (Dougherty Burrowing Crayfish): 13C C. (D.) englishi Hobbs and Hall (Tallapoosa Crayfish): 8P C. (P.) extraneus Hagen (Chickamauga Crayfish): 1R C. (H.) fasciatusA Hobbs (Etowah Crayfish): 9P C. (P.) georgiae Hobbs (Little Tennessee Crayfish): 4B C. (H.) girardianus Faxon (Tanback Crayfish): 1AR C. (D.) halli Hobbs (Slackwater Crayfish): 8P C. (D.) hartiA Hobbs (Piedmont Blue Burrower): 12P, 13P C. (P.) hiwasseensis Hobbs (Hiwassee Crayfish): 3B C. (C.) howardi Hobbs and Hall (Chattahoochee Crayfish): 12P C. (D.) latimanus (LeConte) (Variable Crayfish): 2R, 3B, 5R, 6P, 7BPR, 8P, 9P, 10P, 11CP, 12CP, 13CP, 14CP, 15CP, 17CP C. (H.) longirostris Faxon (Longnose Crayfish): 1A, 3B, 5R C. (H.) manningi Hobbs (Greensaddle Crayfish): 2R, 6R C. (J.) nodosus Bouchard and Hobbs (Knotty Burrowing Crayfish): 3B, 12BP C. (P.) parrishi Hobbs (Hiwassee Headwater Crayfish): 3B C. (J.) parvoculus Hobbs and Shoup (Mountain Midget Crayfish): 1A C. (D.) reflexus Hobbs (Pine Savannah Crayfish): 11C, 17C C. (P.) scotti Hobbs (Chattooga River Crayfish): 5R C. (H.) speciosusA Hobbs (Beautiful Crayfish): 7BR C. (D.) striatus Hay (Ambiguous Crayfish): 1AR, 2BR, 5R, 6R, 7PR, 8P, 9PR, 11P, 12PC, 13PC, 14PC, 15PC C. (D.) strigosusA Hobbs (Lean Crayfish): 10P, 11P C. (D.) truncatusA Hobbs (Oconee Burrowing Crayfish): 15C C. (J.) unestami Hobbs and Hall (Blackbarred Crayfish): 1AR, 5A Distocambarus (D.) devexusA (Hobbs) (Broad River Burrowing Crayfish): 10P, 11P Fallicambarus (Creaserinus) fodiens (Cottle) (Digger Crayfish): 12C Faxonella clypeata (Hay) (Ditch Fencing Crayfish): 12PC, 13C, 14C, 15C, 16C, 17C, 20C Orconectes (Crockerinus) erichsonianus (Faxon) (Reticulate Crayfish): 1AR, 5R, 6R, 7P 138 Southeastern Naturalist Vol. 9, Special Issue 3 O. (Procericambarus) forceps (Faxon) (Surgeon Crayfish): 1R O. (Buannulifictus) palmeri creolanusB (Creaser) (Creole Painted Crayfish): 13C O. (P.) spinosus (Bundy) (Coosa River Spiny Crayfish): 2R, 5R, 6R, 9R Procambarus (Ortmannicus) acutissimus (Girard) (Sharpnose Crayfish): 12CP P. (O.) acutus (Girard) (White River Crawfish): 10P, 13PD, 14C, 15C, 16C, 17C, 21C P. (Hagenides) advenaA (LeConte) (Vidalia Crayfish): 11C, 16C, 17C, 23C, 24C, 25C P. (O.) angustatusC (LeConte) (Sandhills Crayfish) P. (Leconticambarus) barbatus (Faxon) (Wandering Crayfish): 11C, 17C, 23C, 24C, 25C P. (H.) caritusA Hobbs (Poor Crayfish): 14C, 15C, 22C, 23C P. (O.) chacei Hobbs (Cedar Creek Crayfish): 11C, 14C, 17C P. (Scapulicambarus) clarkiiB (Girard) (Red Swamp Crawfish): 9P, 14P, 15P P. (O.) enoplosternum Hobbs (Black Mottled Crayfish): 15C, 16C P. (O.) epicyrtusA Hobbs (Humpback Crayfish): 11C, 17C, 24C P. (O.) fallax (Hagen) (Slough Crayfish): 20C, 21C, 22C P. (Pennides) gibbusA Hobbs (Muckalee Crayfish): 13C P. (O.) hayiB (Faxon) (Straightedge Crayfish): 15P P. (S.) howellaeA Hobbs (Ornate Crayfish): 13C, 14C, 15C, 16C P. (O.) litosternumA Hobbs (Blackwater Crayfish): 17C, 24C, 25C P. (O.) lophotus Hobbs and Walton (Mane Crayfish): 1R, 2R, 5R, 6R P. (O.) lunzi (Hobbs) (Hummock Crayfish): 17C, 22C, 23C, 24C, 25C P. (S.) paeninsulanus (Faxon) (Peninsula Crayfish): 12C, 13C, 18C, 19C, 20C, 21C, 22C P. (Pe.) petersiA Hobbs (Ogeechee Crayfish): 17C, 24C P. (O.) pubescens (Faxon) (Brushnose Crayfish): 10P, 11CP, 15C, 16C, 17CP P. (L.) pubischelae deficiensA Hobbs (Hookless Crayfish): 22C, 23C P. (L.) p. pubischelae Hobbs (Brushpalm Crayfish): 20C, 21C, 22C P. (H.) pygmaeus Hobbs (Christmas Tree Crayfish): 11C, 14C, 17C, 20C, 22C, 23C, 24C, 25C P. (Pe.) raneyi Hobbs (Disjunct Crayfish): 10P, 11CP, 14P P. (O.) seminolae Hobbs (Seminole Crayfish): 13C, 14C, 15C, 16C, 17CD, 20C, 21C, 22C, 23C P. (Pe.) spiculifer (LeConte) (White Tubercled Crayfish): 2R, 6R, 7PR, 8P, 9PR, 11P, 12CP, 13CP, 14CP, 15CP, 16C, 18C, 20C, 21C, 22C P. (H.) talpoides Hobbs (Mole Crayfish): 13C, 18C, 20C, 21C, 22C P. (S.) troglodytes (LeConte) (Eastern Red Swamp Crawfish): 11C, 17C, 23C, 24C, 25C P. (H.) truculentusA Hobbs (Bog Crayfish): 15C, 16C, 17C, 24C P. (O.) verrucosus Hobbs (Grainy Crayfish): 12C P. (Pe.) versutus (Hagen) (Sly Crayfish): 12C