Elliptio crassidens - (Lamarck, 1819)
Elephantear
Taxonomic Status: Accepted
Related ITIS Name(s): Elliptio crassidens (Lamarck, 1819) (TSN 79958)
Unique Identifier: ELEMENT_GLOBAL.2.107062
Element Code: IMBIV14080
Informal Taxonomy: Animals, Invertebrates - Mollusks - Freshwater Mussels
 
Kingdom Phylum Class Order Family Genus
Animalia Mollusca Bivalvia Unionoida Unionidae Elliptio
Genus Size: D - Medium to large genus (21+ species)
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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: Elliptio crassidens
Taxonomic Comments: The classification of the Atlantic Slope species of Elliptio is currently in a state of confusion. Johnson (1970) lumped many named taxa under a single name. Current research is finding many of these synonomized taxa to be valid species. This research is in progress and will result in the recognition of numerous additional taxa in this genus. Considered E. C. INCRASSATUS (Lea, 1840) by Clench and Turner (1956). A highly variable species, even within the Apalachicola River system.
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 26Jan2009
Global Status Last Changed: 25Nov1996
Rounded Global Status: G5 - Secure
Reasons: This species is wide-ranging and common throughout much of its range and is generally stable with some decline in the northern portions.
Nation: United States
National Status: N5 (16Jul1998)
Nation: Canada
National Status: N3 (03Aug2017)

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 (S5), Florida (SNR), Georgia (S5), Illinois (S2), Indiana (S2), Iowa (SX), Kentucky (S4S5), Louisiana (S3), Minnesota (S1), Mississippi (S4), Missouri (S1), Ohio (S1), Oklahoma (SH), Pennsylvania (SH), Tennessee (S5), Virginia (S1), West Virginia (S2), Wisconsin (S1)
Canada Ontario (SU), Quebec (S2)

Other Statuses

IUCN Red List Category: LC - Least concern
American Fisheries Society Status: Currently Stable (01Jan1993)

NatureServe Global Conservation Status Factors

Range Extent: 200,000-2,500,000 square km (about 80,000-1,000,000 square miles)
Range Extent Comments: This species is wide-ranging in eastern U.S. with its southeastern terminus in the Escambia and Apalachicola River drainages in the Florida panhandle. This species occurs in the Mississippi River drainage, from western Pennsylvania west to Wisconsin, south to Missouri), the Alabama River system, and Georgia and northern Florida (Parmalee and Bogan, 1998).

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

Number of Occurrences: > 300
Number of Occurrences Comments: In Minnesota, this species is found in large rivers but is extremely rare with the only extant population near the mouth of the St. Croix River (Sietman, 2003). This species was recorded from the Strong River in Mississippi in 2001 (Darden et al., 2002). In Tennessee, it is currently limited to primarily the Cumberland and Tennessee Rivers and their large tributaries (Elk, Duck, Big South Fork Cumberland, and Holston) in east and middle Tennessee; but is still present in the Loosahatchie River, west Tennessee (Parmalee and Bogan, 1998). It has been collected in Kentucky in the Middle Green and Barren Rivers (Cochran and Layzer, 1993), but is considered occasional to sporadic nearly statewide (Cicerello and Schuster, 2003). In Illinois, it is found sporadically in the Wabash and Ohio Rivers (Cummings and Mayer, 1997). Indiana distribution: Wabash mainstem (historic) and tributaries (current) (Fisher, 2006), East Fork White (Harmon, 1992), Tippecanoe (Cummings and Berlocher, 1990). In Ohio, it is common in the Ohio River and rarer in smaller rivers upstream but not as far as Lake Erie drainages (Watters, 1995); historical in Scioto to Columbus and Tuscarawas at New Philadelphia (Watters et al., 2009). In West Virginia, it occurs in the Upper Ohio/Kanawha (Zeto et al., 1987), Elk, Twelvepole Creek, and Monongahale (possibly extirpated) Rivers, with archaeological evidence from the Ohio River (Taylor and Horn, 1983). In Mississippi, it occurs in the Mississippi River South, Big Black, Tennessee, Lake Pontchartrain, Pearl, Pascagoula, and Tombigbee drainages (Jones et al., 2005). In Louisiana, Vidrine (1993) and Brown and Banks (2001) report it from most drainages in the northern section of eastern Louisiana. It is common in the Amite (Brown and Banks, 2001). In Alabama it is in the Tennessee basin including several tributaries (Ahlstedt, 1996), much of the Mobile basin (except Tallapoosa drainage above the fall line) (Williams et al., 2008), and Bear Creek drainage into Mississippi (McGregor and Garner, 2004). In the ACF basin, it was recently collected from 67 of 324 sites in Alabama, Florida and Georgia in the main channel of the Apalachicola River as well as the main channel and tributaries of the Flint and Chipola Rivers, but only as shells and a single live specimen in the Chattahoochee River system (Little Uchee Creek, Sawhatchee Creek) (Brim-Box and Williams, 2000). Golladay et al. (2004) found this species in decent numbers at 6 of 21 sites (1999) and 7 of 21 sites (2001) in tributary streams of the lower Flint River Basin on the Gulf Coastal Plain in southwest Georgia. In a 2004 survey of 24 sites in the Choctawhatchee, Yellow, and Conecuh-Escambia River drainages in southern Alabama, Pilarczyk et al. (2006) found this species at two sites. This species was recently collected from the Black Warrior River in Tuscaloosa and Greene/Hale Cos. and upper Tombigbee River in Sumter and Greene Cos., Alabama (Williams et al., 1992); also Alabama drainage (McGregor et al., 1999). In the Coosa River basin in Georgia, it is known historically from the Coosa, Etowah, Oostanaula, Conasauga, and Coosawattee River drainages but has not been collected live recently except in the Oostanaula (Williams and Hughes, 2001). Three valves were recently found in Michigan in the Grand River (Badra and Goforth, 2003), and, although they are likely attributable to transport by poachers or dumping by a previous button factory, surveys should be conducted to confirm absence of a live population. In Canada, this species is known from Quebec and Ontario (specific information lacking- likely Castor River in eastern Ontario) but abundance estimates are not known (Metcalfe-Smith and Cudmore-Vokey, 2004).

Population Size: >1,000,000 individuals
Population Size Comments: In the ACF basin, it was recently collected from 67 of 324 sites (500 live, 374 shells) in Alabama, Florida and Georgia in the main channel of the Apalachicola River as well as the main channel and tributaries of the Flint and Chipola Rivers, but only as shells and a single live specimen in th eChattahoochee River system (Little Uchee Creek, Sawhatchee Creek) (Brim-Box and Williams, 2000).

Number of Occurrences with Good Viability/Integrity: Unknown

Overall Threat Impact Comments: Following a recent drought from 1999-2001, this species experienced decline in abundance in the Flint River drainage as evidenced by surveys in 2001 and 2002 (Chastain et al., 2005).

Short-term Trend: Decline of <30% to relatively stable
Short-term Trend Comments: This species has been extirpated from the Minnesota River and likely the Mississippi River in Minnesota (Sietman, 2003) as well as ports of northern Illinois. It is considered stable in the ACF basin (Brim Box and Williams, 2000) and southern portions of its range.

Long-term Trend: Decline of <30% to increase of 25%
Long-term Trend Comments: This species is extirpated in Pennsylvania (Bogan, 1993) where it formerly occurred in the Lower Allegheny, Lower Monongahela, Middle Allegheny-Redbank, and Upper Ohio drainages (Ortmann, 1919).

Intrinsic Vulnerability: Unknown

Environmental Specificity: Broad. Generalist or community with all key requirements common.
Environmental Specificity Comments: This species inhabits muddy sand, sand and rocky substrates in moderate currents (Heard, 1979). It is also an inhabitant of channels. In the ACF basin, it is most common in large creeks to rivers with moderate to swift currents primarily on sand and limestone or rock substrates (Brim Box and Williams, 2000).

Other NatureServe Conservation Status Information

Distribution
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Global Range: (200,000-2,500,000 square km (about 80,000-1,000,000 square miles)) This species is wide-ranging in eastern U.S. with its southeastern terminus in the Escambia and Apalachicola River drainages in the Florida panhandle. This species occurs in the Mississippi River drainage, from western Pennsylvania west to Wisconsin, south to Missouri), the Alabama River system, and Georgia and northern Florida (Parmalee and Bogan, 1998).

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: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AL, FL, GA, IAextirpated, IL, IN, KY, LA, MN, MO, MS, OH, OK, PA, TN, VA, WI, WV
Canada ON, QC

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AL Baldwin (01003), Bibb (01007), Blount (01009)*, Clarke (01025), Conecuh (01035)*, Dallas (01047), Escambia (01053), Geneva (01061), Greene (01063), Jackson (01071), Jefferson (01073), Limestone (01083)*, Madison (01089), Marshall (01095), Morgan (01103), Perry (01105), Pickens (01107), Shelby (01117), Wilcox (01131)
IL Adams (17001)*, Clark (17023)*, Lawrence (17101), Massac (17127), Pike (17149)*, Pulaski (17153), Wabash (17185), White (17193)*
IN Perry (18123)
KY Edmonson (21061)
LA East Feliciana (22037), St. Helena (22091), St. Tammany (22103), Tangipahoa (22105)
MN Carver (27019), Dakota (27037), Goodhue (27049)*, Hennepin (27053)*, Houston (27055), Ramsey (27123), Scott (27139), Wabasha (27157)*, Washington (27163), Winona (27169)
MO Bollinger (29017), Butler (29023), Cedar (29039), Cole (29051), Cooper (29053), Franklin (29071), Gasconade (29073), Jefferson (29099), Maries (29125), Miller (29131), Osage (29151), Pulaski (29169), Ripley (29181), St. Charles (29183), St. Louis (29189), Stone (29209), Wayne (29223)
OH Ashtabula (39007)*, Brown (39015), Clermont (39025), Franklin (39049), Gallia (39053), Hamilton (39061), Lawrence (39087), Madison (39097), Morgan (39115), Pickaway (39129), Ross (39141), Scioto (39145), Washington (39167)
PA Allegheny (42003)*, Armstrong (42005)*, Beaver (42007)*, Washington (42125)*, Westmoreland (42129)*
VA Lee (51105), Russell (51167)*, Scott (51169), Wise (51195)*
WI Buffalo (55011)*, Crawford (55023), Grant (55043), Pepin (55091)*, Pierce (55093), Polk (55095), St. Croix (55109), Trempealeau (55121)*
WV Cabell (54011), Clay (54015), Fayette (54019), Jackson (54035), Kanawha (54039), Mason (54053), Wood (54107)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
03 Pea (03140202)+, Sepulga (03140303)+*, Lower Conecuh (03140304)+, Cahaba (03150202)+, Middle Alabama (03150203)+, Lower Alabama (03150204)+, Sipsey (03160107)+, Locust (03160111)+*, Lower Pearl. Mississippi (03180004)+, Bogue Chitto (03180005)+
04 Grand (04110004)+*
05 Middle Allegheny-Redbank (05010006)+*, Lower Allegheny (05010009)+*, Lower Monongahela (05020005)+*, Upper Ohio (05030101)+*, Upper Ohio-Shade (05030202)+, Muskingum (05040004)+, Upper Kanawha (05050006)+, Elk (05050007)+, Upper Scioto (05060001)+, Lower Scioto (05060002)+, Raccoon-Symmes (05090101)+, Little Scioto-Tygarts (05090103)+, Ohio Brush-Whiteoak (05090201)+, Little Miami (05090202)+, Middle Ohio-Laughery (05090203)+*, Upper Green (05110001)+, Middle Wabash-Busseron (05120111)+, Lower Wabash (05120113)+, Lower Ohio-Little Pigeon (05140201)+, Lower Ohio (05140206)+
06 Upper Clinch (06010205)+, Powell (06010206)+, Wheeler Lake (06030002)+
07 Twin Cities (07010206)+, Lower Minnesota (07020012)+, Upper St. Croix (07030001)+, Lower St. Croix (07030005)+, Rush-Vermillion (07040001)+, Cannon (07040002)+*, Buffalo-Whitewater (07040003)+, Trempealeau (07040005)+*, Coon-Yellow (07060001)+, Lower Wisconsin (07070005)+, The Sny (07110004)+*, Peruque-Piasa (07110009)+, Meramec (07140102)+, Big (07140104)+, Whitewater (07140107)+
08 Amite (08070202)+, Tickfaw (08070203)+, Tangipahoa (08070205)+
10 Sac (10290106)+, Lower Osage (10290111)+, Upper Gasconade (10290201)+, Lower Gasconade (10290203)+, Lamine (10300103)+
11 James (11010002)+, Upper Black (11010007)+, Current (11010008)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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General Description: See Clench and Turner (1956).
Diagnostic Characteristics: A large, thickshelled, dark ELLIPTIO with wrinkling on the sharp ridged posterior slope.
Reproduction Comments: Tachytictic (short-term breeder).
Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: Greatest potential during glochidial stage on fish. Inhabitants of soft substrates presumably have higher mobility potential than inhabitants of rocky substrates.
Riverine Habitat(s): BIG RIVER, CREEK, Low gradient, MEDIUM RIVER, Moderate gradient, Riffle
Lacustrine Habitat(s): Shallow water
Special Habitat Factors: Benthic
Habitat Comments: This species inhabits muddy sand, sand and rocky substrates in moderate currents (Heard, 1979). It is also an inhabitant of channels. In the ACF basin, it is most common in large creeks to rivers with moderate to swift currents primarily on sand and limestone or rock substrates (Brim Box and Williams, 2000).
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: 10 centimeters
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
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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: 26Jan2009
NatureServe Conservation Status Factors Author: Cordeiro, J.
Element Ecology & Life History Edition Date: 14Apr2007
Element Ecology & Life History Author(s): Cordeiro, J. (2007); BUTLER, R.S. (1991)

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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  • Bogan, A.E. 1993a. Workshop on freshwater bivalves of Pennsylvania. Workshop hosted by Aquatic Systems Corporation, Pittsburgh, Pennsylvania, held at Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, 6-7 May 1993. 80 pp.

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  • Strayer, D.L. 1999a. Use of flow refuges by unionid mussels in rivers. Journal of the North American Benthological Society 18(4):468-476.

  • Strayer, D.L. and J. Ralley. 1993. Microhabitat use by an assemblage of stream-dwelling unionaceans (Bivalvia) including two rare species of Alasmidonta. Journal of the North American Benthological Society 12(3):247-258.

  • Taylor, R.W. and K.J. Horn. 1983. A list of freshwater mussels suggested for designation as rare, endangereed or threatened in West Virginia. Proceedings of the West Virginia Academy of Science (Biology Section) 54:31-34.

  • 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.

  • Van der Schalie, H. 1938a. The naiad fauna of the Huron River in southeastern Michigan. Miscellaneous Publication of the Museum of Zoology, University of Michigan 40:7-78.

  • Watters, G. T. 1994. An annotated bibliography of the reproduction and propagation of the Unionoidea (Primarily of North America). Ohio Biological Survey Miscellaneous Contributions No. 1, Columbus, Ohio. 158 pp.

  • Watters, G. Thomas. 1994. An Annotated Bibliography of the Reproduction and Propogation of the Unionoidea (Primarily of North America). Ohio Biological Survey, College of Biological Sciences, The Ohio State University. In cooperation with Ohio Division of Wildlife. 158 pp.

  • Watters, G.T. 1992a. Unionids, fishes, and the species-area curve. Journal of Biogeography 19:481-490.

  • Watters, G.T. 1995a. A field guide to the freshwater mussels of Ohio. revised 3rd edition. Ohio Department of Natural Resources, Division of Wildlife, Columbus, Ohio. 122 pp.

  • 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., 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.

  • 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.

  • Zeto, M.A., W.A. Tolin, and J.E. Schmidt. 1987. The freshwater mussels (Unionidae) of the upper Ohio River, Greenup and Belleville Pools, West Virginia. The Nautilus, 101: 182-185.

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

  • van der Schalie, H., and A. van der Schalie. 1950. The mussels of the Mississippi River. American Midland Naturalist 44:448-464.

References for Watershed Distribution Map
  • Ahlstedt, S.A. 1995-1996. Status survey for federally listed endangered freshwater mussel species in the Paint Rock River system, northeastern Alabama, U.S.A. Walkerana 8(19):63-80.

  • Badra, P.J. and R.R. Goforth. 2003. Freshwater mussel surveys of Great Lakes tributary rivers in Michigan. Report Number MNFI 2003-15 to the Michigan Department of Environmental Quality, Coastal Zone Management Unit, Lansing, Michigan. 40 pp.

  • Brim Box, J. and J.D. Williams. 2000. Unionid mollusks of the Apalachicola Basin in Alabama, Florida, and Georgia. Alabama Museum of Natural History Bulletin, 21: 1-143.

  • 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.

  • Cicerello, R.R. and G.A. Schuster. 2003. A guide to the freshwater mussels of Kentucky. Kentucky State Nature Preserves Commission Scientific and Technical Series 7:1-62.

  • Cummings, K.S. and C.A. Mayer. 1997. Distributional checklist and status of Illinois freshwater mussels (Mollusca: Unionacea). Pages 129-145 in: K.S. Cummings, A.C. Buchanan, C.A. Mayer, and T.J. Naimo (eds.) Conservation and management of freshwater mussels II: initiatives for the future. Proceedings of a UMRCC Symposium, October 1995, St. Louis, Missouri. Upper Mississippi River Conservation Committee, Rock Island, Illinois.

  • Harmon, J.L. 1992. Naiades (Bivalvia: Unionidae) of Sugar Creek, east fork White River drainage, in central Indiana. Malacology Data Net 3(1-4):31-42.

  • Hartfield, H. 1993. Headcuts and their effect on freshwater mussels. Pages 131-141 in K.S. Cummings, A.C. Buchanan, and L.M. Koch. (eds.). Conservation and Management of Freshwater Mussels. Proceedings of a UMRCC Symposium, 12-14 October 1992, St. Louis, Missouri. Upper Mississippi River Conservation Committee, Rock Island, Illinois. 189 pp.

  • Hartfield, P.D. and R.G. Rummel. 1985. Freshwater mussels (Unionidae) of the Big Black River, Mississippi. The Nautilus, 99(4): 116-119.

  • Jones, R.L., W.T. Slack, and P.D. Hartfield. 2005. The freshwater mussels (Mollusca: Bivalvia: Unionidae) of Mississippi. Southeastern Naturalist, 4(1): 77-92.

  • Metcalfe-Smith, J.L. and B. Cudmore-Vokey. 2004. National general status assessment of freshwater mussels (Unionacea). National Water Research Institute / NWRI Contribution No. 04-027. Environment Canada, March 2004. Paginated separately.

  • Mirarchi, R.E., et al. 2004a. Alabama Wildlife. Volume One: A Checklist of Vertebrates and Selected Invertebrates: Aquatic Mollusks, Fishes, Amphibians, Reptiles, Birds, and Mammals. University of Alabama Press: Tuscaloosa, Alabama. 209 pp.

  • Oesch, R.D. 1995. Missouri Naiades. A Guide to the Mussels of Missouri. Second edition. Missouri Department of Conservation: Jefferson City, Missouri. viii + 271 pp.

  • Parmalee, P.W. and A.E. Bogan. 1998. The Freshwater Mussels of Tennessee. University of Tennessee Press: Knoxville, Tennessee. 328 pp.

  • Pilarczyk, M.M., P.M. Stewart, D.N. Shelton, H.N. Blalock-Herod, and J.D. Williams. 2006. Current and Recent historical freshwater mussel assemblages in the Gulf Coastal Plains. Southeastern Naturalist, 5(2): 205-226.

  • Sietman, B.E. 2003. Field Guide to the Freshwater Mussels of Minnesota. Minnesota Department of Natural Resources: St. Paul, Minnesota. 144 pp.

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

  • Watters, G.T., M.A. Hoggarth, and D.H. Stansbery. 2009b. The Freshwater Mussels of Ohio. Ohio State University Press: Columbus, Ohio. 421 pp.

  • 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.

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