Pseudodontoideus subvexus - (Conrad, 1834)
Southern Creekmussel
Synonym(s): Strophitus subvexus (Conrad, 1834)
Taxonomic Status: Accepted
Related ITIS Name(s): Strophitus subvexus (Conrad, 1834) (TSN 80154)
Unique Identifier: ELEMENT_GLOBAL.2.111058
Element Code: IMBIV42020
Informal Taxonomy: Animals, Invertebrates - Mollusks - Freshwater Mussels
 
Kingdom Phylum Class Order Family Genus
Animalia Mollusca Bivalvia Unionoida Unionidae Pseudodontoideus
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Concept Reference
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Concept Reference: Turgeon, D.D., J.F. Quinn, Jr., A.E. Bogan, E.V. Coan, F.G. Hochberg, W.G. Lyons, P.M. Mikkelsen, R.J. Neves, C.F.E. Roper, G. Rosenberg, B. Roth, A. Scheltema, F.G. Thompson, M. Vecchione, and J.D. Williams. 1998. Common and scientific names of aquatic invertebrates from the United States and Canada: Mollusks. 2nd Edition. American Fisheries Society Special Publication 26, Bethesda, Maryland: 526 pp.
Concept Reference Code: B98TUR01EHUS
Name Used in Concept Reference: Strophitus subvexus
Taxonomic Comments: Smith et al. (2018) transfer Strophitus subvexus to Pseudodontoideus.

The taxonomic status, generic and specific, of Strophitus subvexus has varied during the past century. Van der Schalie (1940) reported it as Strophitus spillmanii from the Chipola River drainage, and Clench and Turner (1956) erroneously assumed that these specimens of S. spillmanii were Anodontoides elliottii [= Anodontoides radiatus]. Van der Schalie's specimens of S. spillmanii were later re-identified asS. subvexus by Johnson (1967), who re-examined the systematic and taxonomic questions and recognized only one species of Strophitus on the Gulf Coast. Hence, both van der Schalie's and Clench and Turner's specimens from the Chipola River drainage are S. subvexus. The taxonomic status of Strophitus in western Gulf Coast drainages is unclear as Strecker (1931) reported S. subvexus from eastern Texas but Howells et al. (1996) considered all individuals in the state to be S. undulatus. Meanwhile, Vidrine (1993) suggested that Strophitus from western Louisiana (i.e., those in the Calcasieu and Sabine Rivers) represent an undescribed species similar to S. subvexus. Williams et al. (2008) confined S. subvexus to the Tombigbee and Black Warrior River drainages and S. connasaugensis to eastern drainages of the Mobile Basin, however individuals resembling S. subvexus can sometimes be found ineastern reaches of the Mobile basin and individuals resembling S. connasaugaensis can occasionally be found in the Black Warrior and Tombigbee River drainages.
Conservation Status
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NatureServe Status

Global Status: G3
Global Status Last Reviewed: 19May2009
Global Status Last Changed: 31Aug2000
Rounded Global Status: G3 - Vulnerable
Reasons: This species occurs in multiple drainages along the Gulf coast, although it appears to be extirpated from some historic localities and is declining in several others where it is considered threatened.
Nation: United States
National Status: N3 (31Aug2000)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alabama (S3), Louisiana (S1), Mississippi (S2), Texas (SNR)

Other Statuses

IUCN Red List Category: NT - Near threatened
American Fisheries Society Status: Special Concern (01Jan1993)

NatureServe Global Conservation Status Factors

Range Extent: 5000-20,000 square km (about 2000-8000 square miles)
Range Extent Comments: It occurs in the Mobile Basin, the Tangipahoa River of the lake Pontchartrain drainage and a tributary of the Mississippi River in extreme southwestern Mississippi (Vidrine, 1993; Jones et al., 2005; Williams et al., 2008). The taxonomic status of Strophitus in the Calcasieu and Sabine River drainages of western Louisiana is unclear (Vidrine, 1993; Howells et al., 1996). Howells et al. (1996) list all Texas Strophitus as Strophitus undulatus but notes that eastern drainage species should be examined to be sure. The taxonomic status of Strophitus in the Calcasieu and Sabine River drainages of western Louisiana is unclear (Vidrine, 1993; Howells et al., 1996). Williams et al. (2008) confined the distribution of Strophitus connasaugaensis to eastern drainages of the Mobile Basin (as far northeast as Georgia), and that of Strophitus subvexus to the Tombigbee and Black Warrior River drainages, however, individuals of each species may be found within the range of the other so it is unclear if the two species occur sympatrically or not. Reports of the species in Gulf Coast drainages east of the Mobile Basin (e.g. van der Schalie, 1940; Johnson, 1967; Williams and Hughes, 1998; Brim Box and Williams, 2000; Blalock et al., 1998; Williams et al., 2000; Galladay et al., 2004) have been determined by genetic analyses to be Anodontoides radiatus (H.-P. Liu, pers. comm., in Williams et al., 2008).

Area of Occupancy: 2,501 to >12,500 4-km2 grid cells
Area of Occupancy Comments:  

Number of Occurrences: 21 - 80
Number of Occurrences Comments: Reports of the species in Gulf Coast drainages east of the Mobile Basin in the ACF basin of Alabama, Florida, and Georgia (van der Schalie, 1940; Johnson, 1967; Williams and Hughes, 1998; Brim Box and Williams, 2000) and Choctawhatchee-Escambia systems (Blalock et al., 1998; Williams et al., 2000; Golladay et al., 2004) have been determined by genetic analyses to be Anodontoides radiatus (H.-P. Liu, pers. comm., in Williams et al., 2008). Historical occurrences cited by Johnson (1967) include the following: Pascagoula River drainage: Mississippi; Tombigbee River drainage: Mississippi, Alabama; and Cahawba River drainage: Alabama. Reports by Johnson (1967) in the Apalachicola River system (Chipola River, Florida), have been determined by genetic analyses to be Anodontoides radiatus (H.-P. Liu, pers. comm., in Williams et al., 2008). Johnson's (1967) citations for the Coosa River drainage (Georgia, Alabama, Tennessee), Tallapoosa River drainage (Alabama), and Alabama River drainage (Alabama) have been designated by Williams et al. (2008) to be Strophitus connasaugaensis. Mirarchi (2004) cites Alabama distribution as throughout the state south of the Tennessee River system particularly the Black Warrior and Tombigbee River drainages (Williams et al., 2008). Kennedy and Haag (2005) cite specimens from Brushy Creek, Lawrence Co., Alabama. This species was recently collected from the Black Warrior River in Tuscaloosa and Greene/Hale Cos. and is historically known from the upper Tombigbee River in Sumter and Greene Cos., Alabama (Williams et al., 1992). Vidrine (1993) cites Louisiana distribution as occurring in southwestern to central Louisiana (Calcasieu and Sabine River drainages possibly west to the Jacinto, Coloarado, and Brazos Rivers). Brown and Banks (2001) list 1990s records for the Amite and Tangipahoa Rivers. Jones et al. (2005) cites the Tombigbee River basin in Mississippi. Howells et al. (1996) list all Texas Strophitus as Strophitus undulatus but notes that eastern drainage species should be examined to be sure.

Population Size: 10,000 - 100,000 individuals
Population Size Comments: Little is known about the historical abundance of this species in any part of its range, although van der Schalie (1940) considered it rare in the Chipola River drainage, based on a 1915 to 1918 survey, where only two specimens were found (Brim Box and Williams, 2000). Only six occurrences were located in a recent survey of 324 sites in the ACF Basin. In 1999, this species was found to comprise 0.07% (relative abundance) of the 14,873 mussels collected in surveys of 46 sites in 12 tributary streams of the lower Flint River Basin, Georgia (Gagnon et al., 2006). In 1999 and 2001, this species was found in 10 sites (10 specimens) and 9 sites (5 specimens), respectively, in surveys of 5 sites (each year) in about a dozen tributary streams of the lower Flint River Basin, in southwestern Georgia (Golladay et al., 2004).

Number of Occurrences with Good Viability/Integrity: Very few to few (1-12)
Viability/Integrity Comments: In 1999 and 2001, this species was found in 10 sites (10 specimens) and 9 sites (5 specimens), respectively, in surveys of 5 sites (each year) in about a dozen tributary streams of the lower Flint River Basin, in southwestern Georgia (Golladay et al., 2004).

Overall Threat Impact: High
Overall Threat Impact Comments: This species appears to be most common in mid-channel river habitats that are most often impacted by excess sedimentation and overall channel modifications. Impoundments, water withdrawls, urbanization, and point and non-point pollution are all possible threats. Following a recent drought from 1999-2001, this species experienced decline in abundance in the Flint River drainage in Georgia as evidenced by surveys in 2001 and 2002 (Chastain et al., 2005).

Short-term Trend: Decline of 10-30%

Long-term Trend: Decline of 30-50%
Long-term Trend Comments: It was extirpated historically from the Tennessee River system in Alabama (Mirarchi, 2004).

Intrinsic Vulnerability: Unknown

Environmental Specificity: Moderate. Generalist or community with some key requirements scarce.
Environmental Specificity Comments: It is found in small to large creeks, in substrates from sand to sandy mud, in slow or no current (Deyrup and Franz, 1994). In the ACF Basin it is found in sandy substrates associated with some current (Brim Box and Williams, 2000), however Clench and Turner (1956) indicated it appeared to prefer backwater areas of rivers and slow-flowing large creeks.

Other NatureServe Conservation Status Information

Inventory Needs: Surveys of historical occurrences in western part of historical range (e.g., Sabine River in Louisiana and Texas) are needed.

Distribution
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Global Range: (5000-20,000 square km (about 2000-8000 square miles)) It occurs in the Mobile Basin, the Tangipahoa River of the lake Pontchartrain drainage and a tributary of the Mississippi River in extreme southwestern Mississippi (Vidrine, 1993; Jones et al., 2005; Williams et al., 2008). The taxonomic status of Strophitus in the Calcasieu and Sabine River drainages of western Louisiana is unclear (Vidrine, 1993; Howells et al., 1996). Howells et al. (1996) list all Texas Strophitus as Strophitus undulatus but notes that eastern drainage species should be examined to be sure. The taxonomic status of Strophitus in the Calcasieu and Sabine River drainages of western Louisiana is unclear (Vidrine, 1993; Howells et al., 1996). Williams et al. (2008) confined the distribution of Strophitus connasaugaensis to eastern drainages of the Mobile Basin (as far northeast as Georgia), and that of Strophitus subvexus to the Tombigbee and Black Warrior River drainages, however, individuals of each species may be found within the range of the other so it is unclear if the two species occur sympatrically or not. Reports of the species in Gulf Coast drainages east of the Mobile Basin (e.g. van der Schalie, 1940; Johnson, 1967; Williams and Hughes, 1998; Brim Box and Williams, 2000; Blalock et al., 1998; Williams et al., 2000; Galladay et al., 2004) have been determined by genetic analyses to be Anodontoides radiatus (H.-P. Liu, pers. comm., in Williams et al., 2008).

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
Endemism: endemic to a single nation

U.S. & Canada State/Province Distribution
United States AL, LA, MS, TX

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AL Choctaw (01023), Fayette (01057), Greene (01063), Lamar (01075), Lawrence (01079), Pickens (01107), Tuscaloosa (01125), Walker (01127)*, Winston (01133)
LA Ascension (22005), Beauregard (22011)*, Calcasieu (22019)*, Livingston (22063), Rapides (22079), Vernon (22115), Winn (22127)
MS Clay (28025)*, Itawamba (28057), Lowndes (28087), Monroe (28095)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
03 Chipola (03130012)*, Upper Tombigbee (03160101)+, Town (03160102), Buttahatchee (03160103)+, Luxapallila (03160105)+, Middle Tombigbee-Lubbub (03160106)+, Sipsey (03160107)+, Noxubee (03160108), Mulberry (03160109)+, Sipsey Fork (03160110)+, Locust (03160111), Upper Black Warrior (03160112)+, Lower Black Warrior (03160113), Middle Tombigbee-Chickasaw (03160201)+, Lower Tambigbee (03160203), Upper Pearl (03180001)*, Lower Pearl. Mississippi (03180004)
08 Dugdemona (08040303)+, Little (08040304), Bayou Pierre (08060203), Amite (08070202)+, Tangipahoa (08070205), Upper Calcasieu (08080203)+, Whisky Chitto (08080204)+, Liberty Bayou-Tchefuncta (08090201)
11 Middle Red-Coushatta (11140202)
12 Toledo Bend Reservoir (12010004), Lower Sabine (12010005)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
U.S. Distribution by Watershed (based on multiple information sources) Help
Ecology & Life History
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Basic Description: a freshwater mussel
General Description: See Johnson (1967) and Deyrup and Franz (1994).
Diagnostic Characteristics: Thin shelled, each valve has a very low, stumpy pseudocardinal tooth, lateral teeth are absent.
Reproduction Comments: Freshwater mussel larvae (glochidia) are brooded in the gills of the female and when mature are released into the water where they spend a brief period as obligate parasites on the gills, fins, or other external parts of fish until they drop off to the benthos. Haag and Warren (1997) found Strophitus subvexus can use a wide variety of fish species as its host. In the laboratory, ten fish species from the families Cyprinidae, Catostomidae, Fundulidae, Centrarchidae, and Percidae were identified as hosts including Campostoma oligolepis (largescale stoneroller), Cyprinella callista (Alabama shiner), Etheostoma douglasi (Tuscaloosa Darter), Fundulus olivaceus (blackspotted topminnow), Hypentelium etowanum (Alabama hog sucker), Lepomis megalotis (longear sunfish), Micropteris salmoides (largemouth bass), Percina nigrofasciata (blackbanded darter), Semotilus atromaculatus (creek chub), and Pomoxis sp. Females were found gravid with mature glochidia from late February to mid March in water temperatures of 8-13 degrees C (Haag and Warren, 1996; 1997).
Ecology Comments: An enigmatic species with a sporadic distribution in the Apalachicolan region in general. Inhabits creeks and rivers in soft substrates, usually without much current. Can supposedly tolerate some siltation.
Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: Greatest potential during glochidial stage on fish. Adults of this species are essentially sessile. Some passive movement downstream may occur during high flows.
Riverine Habitat(s): CREEK, Low gradient, MEDIUM RIVER, Moderate gradient, Pool, Riffle
Special Habitat Factors: Benthic
Habitat Comments: It is found in small to large creeks, in substrates from sand to sandy mud, in slow or no current (Deyrup and Franz, 1994). In the ACF Basin it is found in sandy substrates associated with some current (Brim Box and Williams, 2000), however Clench and Turner (1956) indicated it appeared to prefer backwater areas of rivers and slow-flowing large creeks.
Adult Food Habits: Detritivore
Immature Food Habits: Parasitic
Food Comments: Presumably fine particulate organic matter, primarily detritus, and/or zooplankton, and/or phytoplankton (Fuller, 1974). Larvae (glochidia) of freshwater mussels generally are parasitic on fish and there may be a specificity among some species.
Length: 9 centimeters
Economic Attributes Not yet assessed
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Management Summary
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Biological Research Needs: Host fish have been identified in the Black Warrior drainage in Alabama (Haag and Warren, 1997), but several of those fish species do not occur in the eastern part of the range of Strophitus subvexus, so information is needed on additional hosts. Research needs to be conducted to differentiate this species from Anodontoides radiatus based on genetics and morphological characters, especially of the conglutinates.
Population/Occurrence Delineation
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Group Name: Freshwater Mussels

Use Class: Not applicable
Minimum Criteria for an Occurrence: Occurrences are based on some evidence of historical or current presence of single or multiple specimens, including live specimens or recently dead shells (i.e., soft tissue still attached and/or nacre still glossy and iridescent without signs of external weathering or staining), at a given location with potentially recurring existence. Weathered shells constitute a historic occurrence. Evidence is derived from reliable published observation or collection data; unpublished, though documented (i.e. government or agency reports, web sites, etc.) observation or collection data; or museum specimen information.
Mapping Guidance: Based on the separation distances outlined herein, for freshwater mussels in STANDING WATER (or backwater areas of flowing water such as oxbows and sloughs), all standing water bodies with either (1) greater than 2 km linear distance of unsuitable habitat between (i.e. lotic connections), or (2) more than 10 km of apparently unoccupied though suitable habitat (including lentic shoreline, linear distance across water bodies, and lentic water bodies with proper lotic connections), are considered separate element occurrences. Only the largest standing water bodies (with 20 km linear shoreline or greater) may have greater than one element occurrence within each. Multiple collection or observation locations in one lake, for example, would only constitute multiple occurrences in the largest lakes, and only then if there was some likelihood that unsurveyed areas between collections did not contain the element.

For freshwater mussels in FLOWING WATER conditions, occurrences are separated by a distance of more than 2 stream km of unsuitable habitat, or a distance of more than 10 stream km of apparently unoccupied though suitable habitat. Standing water between occurrences is considered suitable habitat when calculating separation distance for flowing water mussel species unless dispersal barriers (see Separation Barriers) are in place.

Several mussel species in North America occur in both standing and flowing water (see Specs Notes). Calculation of separation distance and determination of separation barriers for these taxa should take into account the environment in which the element was collected. Juvenile mussels do not follow this pattern and juveniles are typically missed by most standard sampling methods (Hastie and Cosgrove, 2002; Neves and Widlak, 1987), therefore juvenile movement is not considered when calculating separation distance.

Separation Barriers: Separation barriers within standing water bodies are based solely on separation distance (see Separation Distance-suitable, below). Separation barriers between standing water bodies and within flowing water systems include lack of lotic connections, natural barriers such as upland habitat, absence of appropriate species specific fish hosts, water depth greater than 10 meters (Cvancara, 1972; Moyle and Bacon, 1969) or anthropogenic barriers to water flow such as dams or other impoundments and high waterfalls.
Separation Distance for Unsuitable Habitat: 2 km
Separation Distance for Suitable Habitat: 10 km
Alternate Separation Procedure: None
Separation Justification: Adult freshwater mussels are largely sedentary spending their entire lives very near to the place where they first successfully settled (Coker et al., 1921; Watters, 1992). Strayer (1999) demonstrated in field trials that mussels in streams occur chiefly in flow refuges, or relatively stable areas that displayed little movement of particles during flood events. Flow refuges conceivably allow relatively immobile mussels to remain in the same general location throughout their entire lives. Movement occurs with the impetus of some stimulus (nearby water disturbance, physical removal from the water such as during collection, exposure conditions during low water, seasonal temperature change or associated diurnal cycles) and during spawning. Movement is confined to either vertical movement burrowing deeper into sediments though rarely completely beneath the surface, or horizontal movement in a distinct path often away from the area of stimulus. Vertical movement is generally seasonal with rapid descent into the sediment in autumn and gradual reappearance at the surface during spring (Amyot and Downing, 1991; 1997). Horizontal movement is generally on the order of a few meters at most and is associated with day length and during times of spawning (Amyot and Downing, 1997). Such locomotion plays little, if any, part in the distribution of freshwater mussels as these limited movements are not dispersal mechanisms. Dispersal patterns are largely speculative but have been attributed to stream size and surface geology (Strayer, 1983; Strayer and Ralley, 1993; van der Schalie, 1938), utilization of flow refuges during flood stages (Strayer, 1999), and patterns of host fish distribution during spawning periods (Haag and Warren, 1998; Watters, 1992). Lee and DeAngelis (1997) modeled the dispersal of freshwater into unoccupied habitats as a traveling wave front with a velocity ranging from 0.87 to 2.47 km/year (depending on mussel life span) with increase in glochidial attachment rate to fish having no effect on wave velocity.

Nearly all mussels require a host or hosts during the parasitic larval portion of their life cycle. Hosts are usually fish, but a few exceptional species utilize amphibians as hosts (Van Snik Gray et al., 2002; Howard, 1915) or may metamorphose without a host (Allen, 1924; Barfield et al., 1998; Lefevre and Curtis, 1911; 1912). Haag and Warren (1998) found that densities of host generalist mussels (using a variety of hosts from many different families) and displaying host specialists (using a small number of hosts usually in the same family but mussel females have behavioral modifications to attract hosts to the gravid female) were independent of the densities of their hosts. Densities of non-displaying host specialist mussels (using a small number of hosts usually in the same family but without host-attracting behavior) were correlated positively with densities of their hosts. Upstream dispersal of host fish for non-displaying host specialist mussels could, theoretically, transport mussel larvae (glochidia) over long distances through unsuitable habitat, but it is unlikely that this occurs very often. D. Strayer (personal communication) suggested a distance of at least 10 km, but a greater distance between occurrences may be necessary to constitute genetic separation of populations. As such, separation distance is based on a set, though arbitrary, distance between two known points of occurrence.

Date: 18Oct2004
Author: Cordeiro, J.
Notes: Contact Jay Cordeiro (jay_cordeiro@natureserve.org) for a complete list of freshwater mussel taxa sorted by flow regime.
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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NatureServe Conservation Status Factors Edition Date: 19May2009
NatureServe Conservation Status Factors Author: Cordeiro, J. (2009); J. Brim Box, and C. O'Brien (2000)
Element Ecology & Life History Edition Date: 10Apr2007
Element Ecology & Life History Author(s): Cordeiro, J. (2007); BUTLER, R.S. (2000)

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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  • Chastain, C.A., S.W. Golladay, and T.K. Muenz. 2005. Distribution of unionid mussels in tributaries of the lower Flint River, southwestern Georgia: an examination of current and historical trends. Presented at the Proceedings of the 2005 Georgia Water Resources Conference, 25-27 April 2005, University of Georgia.

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  • Williams, J. D., A. E. Bogan, R. S. Butler, K. S. Cummings, J. T. Garner, J. L. Harris, N. A. Johnson, and G. T. Watters. 2017. A revised list of the freshwater mussels (Mollusca: Bivalvia: Unionida) of the United States and Canada. Freshwater Mollusk Biology and Conservation 20:33-58.

  • Williams, J. D., A. E. Bogan, and J. T Garner. 2008. Freshwater mussels of Alabama & the Mobile Basin in Georgia, Mississippi, & Tennessee. University of Alabama Press, Tuscaloosa, Alabama. 908 pages.

  • Williams, J.D. and M.H. Hughes. 1998. Freshwater mussels of selected reaches of the main channel rivers in the Coosa drainage of Georgia. U.S. Geological report to U.S. Army Corps of Engineers, Mobile District, Alabama. 21 pp.

  • Williams, J.D. and R.S. Butler. Freshwater mussels. Vol. 6, Invertebrates. R Frantz, ed. Rare and endangered biota of Florida. FL Committee on Rare and Endangered Plants and Animals, Univ. Presses of FL. In press.

  • Williams, J.D., H.N. Blalock, A. Benson, and D.N. Shelton. 2000. Distribution of the freshwater mussel fauna (Bivalvia: Margaritiferidae and Unionidae) in the Escambia and Yellow river drainages in southern Alabama and western Florida. Final Report for the U.S. Fish and Wildlife Service, Jacksonville, Florida. 61 pp.

  • Williams, J.D., M.L. Warren, Jr., K.S. Cummings, J.L. Harris, and R.J. Neves. 1993b. Conservation status of freshwater mussels of the United States and Canada. Fisheries 18(9): 6-22.

  • van der Schalie, H. 1940. The naiad fauna of the Chipola River in northwestern Florida. Lloydia 3(3):191-208.

References for Watershed Distribution Map
  • Biological Resources Division, USGS. 1997. Database of museum records of aquatic species. Compiled by J. Williams (USGS-BRD, Gainesville, FL).

  • Brown, K.M. and P.D. Banks. 2001. The conservation of unionid mussels in Louisiana rivers: diversity, assemblage composition and substrate use. Aquatic Conservation: Marine and Freshwater Ecosystems, 11(3): 189-198.

  • Haag, W. R. and M. L. Warren, Jr. 1995. Current distributional information on freshwater mussels (family Unionidae) in Mississippi National Forests. U.S. Forest Service General Technical Report S0-119. New Orleans, LA USDA Forest Service, 10 pp.

  • McGregor, S.W., et. al. 1996. Survey of the primary tributaries of the Alabama and lower Tombigbee Rivers for listed and candidate species of mussels, snails, and crayfish: 1994-96.

  • Mirarchi, R.E., J.T. Garner, M.F. Mettee, and P.E. O'Neil. 2004b. Alabama wildlife. Volume 2. Imperiled aquatic mollusks and fishes. University of Alabama Press, Tuscaloosa, Alabama. xii + 255 pp.

  • Vidrine, M. F. 1997. Distribution of freshwater mussels in relation to water quality in two tributaries of Sixmile Creek and Birds Creek, Fort Polk, Louisiana. Final Report. U.S. Geological Survey, Baton Rouge, Louisiana.

  • Vidrine, M.F. 1993. The Historical Distributions of Freshwater Mussels in Louisiana. Gail Q. Vidrine Collectibles: Eunice, Louisiana. xii + 225 pp. + 20 plates.

  • Williams, J.D., A.E. Bogan, and J.T. Garner. 2008. Freshwater Mussels of Alabama & the Mobile Basin in Georgia, Mississippi & Tennessee. University of Alabama Press: Tuscaloosa, Alabama. 908 pp.

  • Williams, J.D., S.L.H. Fuller, and R. Gracea. 1992a. Effects of impoundment on freshwater mussels (Mollusca: Bivalvia: Unionidae) in the main channel of the Black Warrior and Tombigbee Rivers in western Alabama. Bulletin of the Alabama Museum of Natural History 13:1-10.

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