Elliptio chipolaensis - (Walker, 1905)
Chipola Slabshell
Other English Common Names: Chipola slabshell
Taxonomic Status: Accepted
Related ITIS Name(s): Elliptio chipolaensis (Walker, 1905) (TSN 79956)
Unique Identifier: ELEMENT_GLOBAL.2.118225
Element Code: IMBIV14310
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 chipolaensis
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. Possibly large genetic differences exist between populations in the same habitats but different drainages (Davis, 1981; Kat et. al., 1984). This species resembles Elliptio nigella, its counterpart in the Flint and Chattahoochee rivers (both species are endemic to Apalachicola River system); but needs genetic validation.
Conservation Status
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NatureServe Status

Global Status: G1
Global Status Last Reviewed: 09Jan2014
Global Status Last Changed: 09Nov2000
Rounded Global Status: G1 - Critically Imperiled
Reasons: This species has declined significantly, with a loss of more than 75% of historic sites, and is confined to only a few remaining sites in a single drainage of limited extent (about 100 km); only one site hasg good viability. Populations are steadily declining and face continued threats. Critical habitat has been designated along the single remaining watershed where the species occurs.
Nation: United States
National Status: N1 (09Nov2000)

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 (S1), Florida (S1)

Other Statuses

U.S. Endangered Species Act (USESA): LT: Listed threatened (16Mar1998)
U.S. Fish & Wildlife Service Lead Region: R4 - Southeast
IUCN Red List Category: EN - Endangered
American Fisheries Society Status: Threatened (01Jan1993)

NatureServe Global Conservation Status Factors

Range Extent: 100-1000 square km (about 40-400 square miles)
Range Extent Comments: This species was once thought to be endemic to the Chipola River system (van der Schalie, 1940) until Brim Box and Williams (2000) located a single museum specimen from a Chattahoochee River tributary (Howards Mill Creek) in southeastern Alabama and southwestern Georgia; however, that population is believed to have been extirpated. The historic range is centered throughout much of the Chipola River mainstem and several of its headwater tributaries at 17 historic sites. Populations in Dead Lake and Cowarts and Spring creeks (Chipola River) may also be extirpated (USFWS, 2003; Mirarchi et al., 2004), leaving only about 100 km of occupied habitat left in the Chipola River drainage.

Area of Occupancy: 26-500 4-km2 grid cells
Area of Occupancy Comments: The threatened Chipola slabshell currently persists in most of its historic extent of occurrence (83 of 113 river miles), but is reduced to 6 subpopulations of doubtful viability within that range (USFWS, 2003). Linear occupancy is 40-200 km.

Number of Occurrences: 1 - 5
Number of Occurrences Comments: Occupied range includes only about 60 miles (100 km) of the Chipola River system and hence represents one occurrence. A status survey conducted between 1991-1993, that covered at least 75% of all historic sites, found it at five sites (USFWS, 1998). Currently, six sites are known from Marshall and Dry creeks and the upper two-thirds of the Chipola River main stem (USFWS, 2003). The only remaining extant populations in the Chipola River headwaters are at Big and Cowarts Creeks (Williams et al., 2008). The Howards Mill Creek (Chattahoochee River, Alabama) population discovered through a museum specimen by Brim Box and Williams (2000) is now extirpated.

Population Size: 1000 - 2500 individuals
Population Size Comments: Surveys of the Chipola River conducted in the early 1990s found a total of 12 individuals (Brim Box and Williams, 2000). Previously at the same stie, eight specimens were found in 2.5 hours of searching (USFWS, 1998).

Number of Occurrences with Good Viability/Integrity: None to very few (0-3)
Viability/Integrity Comments: The species historically and presently is considered rare (Clench and Turner, 1956; Heard, 1988). Dead Lake Dam was removed in late 1987, returning the upper Chipola River to a free-flowing state. The species currently persists in most of its historic extent of occurrence (83 of 113 river miles) but is known from only 6 subpopulations with doubtful viability (USFWS, 2003). Relative abundance is very low. Butler and Alam (1999) estimated an average of 3.7 individuals per site, with the largest population on the Chipola River main stem in the vicinity of Dead Lake.

Overall Threat Impact: Very high - high
Overall Threat Impact Comments: This species is highly restricted in distribution, occurs in generally small subpopulations, and shows little evidence of recovering from historical habitat losses without significant positive human intervention. Principal causes of decline include impoundments, channelization, pollution, and sedimentation that have altered or eliminated habitats that are essential to the long-term viability of many riverine mussel populations. Detailed information on these threats can be found in USFWS (2003) and include: (1) exploitation by native Americans and for pearls and pearl buttons plus overcollection for scientific purposes (very localized, low impact, historical only); (2) habitat alteration- impoundment causing loss of habitat, loss of shoal habitat, thermal alterations, daily discharge fluctuations, bank sloughing, seasonal oxygen deficiencies, coldwater releases, turbulence, high silt loads, and altered host fish distribution (widespread, high impact, ongoing); (3) impoundment- channelization for navigation and maintenance causing sedimentation and contamination (moderate scope, high impact, historical and ongoing); (4) habitat alteration- gravel mining causing riparian forest clearing, channel modification, disrupted flow, water quality modification, impacts on host fish populations, substrate disturbance/siltation, pollution (moderate scope, high impact, historical and ongoing); (5) contaminants- heavy metals, arsenic and ammonia from poultry and animal feedlots, industrial/municipal effluent, agricultural nutrient enrichment from poultry farms and livestock feedlots, herbicides/pesticides, nutrients from aquaculture ponds, urban stormwater runoff, municipal waste discharge (high-moderate scope, high impact, historical and ongoing); (6) sedimentation- from agricultural, silvicultural, and roadway activities, clearing of riparian vegetation, and flood control activities, gravel mining, livestock grazing (high-moderate scope, high impact, historical and ongoing); (7) urbanization- highways, infrastructure, recreational activities (low scope, moderate-low impact, historical and ongoing); (8) "deadhead logging"- disruption of habitat, increased sediment (localized in Florida only, moderate impact, potential future threat); (9) water withdrawal- mostly for irrigation (moderate impact, moderate scope, ongoing); and (10) introduced species- Asiatic clam, zebra mussel, black carp (moderate-low scope, moderate impact, ongoing). Many of the impacts discussed in USFWS (2003) occurred in the past in conjunction with human development of the Apalachicolan Region. However, the species and its habitats continue to be impacted by excessive sediment bed loads of smaller sediment particles, changes in turbidity, increased suspended solids (primarily resulting from nonpoint-source loading from poor land-use practices, lack of BMPs, and maintenance of existing BMPs), and pesticides.

Short-term Trend: Decline of 50-70%
Short-term Trend Comments: This species is apparently declining. Historically, it was known from 17 sites, but now from only four to six (Brim Box and Williams, 2000). It was probably always uncommon, as are most Elliptio species. It is extirpated from Howards Mill Creek in the Chattahoochee River system, Cowarts and Spring creeks (Chipola River tributaries), and Dead Lake on the lower main stem of the Chipola River (Butler and Alam, 1999).

Long-term Trend: Decline of 70-90%
Long-term Trend Comments: The species currently persists in most of its historic extent of occurrence (83 of 113 rm) but is reduced to 6 subpopulations with doubtful viability (USFWS, 2003). Once locally abundant in the Chipola River in Florida and Alabama, it is nearly extirpated today. The only occurrence from outside the Chipola River drainage (Howard's Mill Creek, a Chattahoochee River tributary in Houston Co., Alabama) is likely extirpated (Williams et al., 2008).

Intrinsic Vulnerability: Highly to moderately vulnerable.
Intrinsic Vulnerability Comments: Freshwater mussels are inherently vulnerable to threats from siltation, pollution, eutrophication, channelization, impoundment, collection, drought and water withdrawal, competiton from invasive non-native mussels, and changes to larval host fish populations. This species is characterized by slow growth to reproductive maturity.

Environmental Specificity: Narrow to moderate.
Environmental Specificity Comments: The Chipola slabshell displays some environmental specificity, inhabiting silty sand substrates of large creeks and the main channel of the Chipola River in slow to moderate current (Williams and Butler, 1994). Specimens are generally found on sloping bank habitats. Nearly 70 percent of the specimens found during the status survey were associated with a sandy substrate (Brim Box and Williams, 2000).

Other NatureServe Conservation Status Information

Inventory Needs: A systematic survey of appropriate habitat throughout the range is necessary to refine knowledge of the species' distribution and identify threats and conservation opportunities. Examine quantitative abundance of all life stages, and check for gravid adults.

Protection Needs: Maintain high water and benthic habitat (substrate) qualities, as well as adequate flow regimes, throughout the Apalachicola River system, but especially in the Chipola River. This may be partially accomplished via establishment of buffers and streamside management zones for all agricultural, silvicultural, mining, and developmental activities; protection of floodplain forests and adjoining upland habitat is paramount. Best management practices to follow include employing forestry practices that cause minimal soil erosion; preventing access of livestock to natural surface waters and drains; situating roads at least 0.25 mi. (0.4 km) from heads of all tributaries, even more on steep slopes; using silt fencing and vegetation to control runoff and siltation at all stream crossings, especially during construction and maintenance; using and maintaining sewer systems rather than septic tanks and stream-dumping for management of wastewater; and avoiding use of agricultural pesticides on porous soils near streams. Prevent damming, dredging, and pollution throughout drainages, but especially near recorded sites. Remove existing dams, but with great care to limit downstream sedimentation. Limit withdrawal of surface and subterranean waters as necessary to maintain normal stream flows, especially during drought. Prevent or limit establishment of invasive species (including zebra mussel, Dreissena polymorpha) to the extent possible. Where appropriate, protect populations through acquisitions and easements over streamside lands by working with government agencies and conservation organizations. Management of the Apalachicola River system must address multiple threats, especially water withdrawal in the state of Georgia, although this may have lesser effect on the Chipola than the Apalachicola itself. See also the detailed USFWS (2003) recovery plan.

Distribution
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Global Range: (100-1000 square km (about 40-400 square miles)) This species was once thought to be endemic to the Chipola River system (van der Schalie, 1940) until Brim Box and Williams (2000) located a single museum specimen from a Chattahoochee River tributary (Howards Mill Creek) in southeastern Alabama and southwestern Georgia; however, that population is believed to have been extirpated. The historic range is centered throughout much of the Chipola River mainstem and several of its headwater tributaries at 17 historic sites. Populations in Dead Lake and Cowarts and Spring creeks (Chipola River) may also be extirpated (USFWS, 2003; Mirarchi et al., 2004), leaving only about 100 km of occupied habitat left in the Chipola River drainage.

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, FL

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AL Houston (01069)
FL Calhoun (12013), Gulf (12045), Jackson (12063)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
03 Lower Chattahoochee (03130004)*, Apalachicola (03130011)+*, Chipola (03130012)+
+ 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 medium-sized freshwater mussel with a chestnut-colored shell.
General Description: See Deyrup and Franz (1994) for full description. Shell is ovate to subelliptical, somewhat inflated and with the posterior ridge starting out rounded, but flattening to form a prominent biangulate margin. Surface is smooth and chestnut colored. Dark brown coloration may appear in the umbonal region and the remaining surface may exhibit alternating light and dark bands. The umbos are prominent, well above the hingeline. Umbonal cavity is deep. The lateral teeth are long, slender, and slightly curved; wto in the left and one in the right valve. Pseudocardinal teeth are compressed and crenulate; two in the left and one in the right valve. Nacre color is salmon, becoming more intense dorsally and somewhat iridescent posteriorly (Butler and Alam, 1999).

From USFWS (2003):
The Chipola slabshell is a medium-sized species reaching a length of about 3.3 in (8.4 cm). The shell is ovate to subelliptical, somewhat inflated, and with the posterior ridge starting out rounded but flattening to form a prominent biangulate margin. The periostracum is smooth and chestnut colored. Dark brown coloration may appear in the umbonal region and the remaining surface may exhibit alternating light and dark bands. The umbos are prominent, well above the hingeline. As is typical of all Elliptio mussels, no sexual dimorphism is displayed in shell characters. Internally, the umbone cavity is rather deep. The lateral teeth are long, slender, and slightly curved, with two in the left and one in the right valve. The pseudocardinal teeth are compressed and crenulate, with two in the left and one in the right valve. Nacre color is salmon, becoming more intense dorsally and somewhat iridescent posteriorly.

Diagnostic Characteristics: Only species with light and dark bands on perio and with salmon-nacre in range.
Reproduction Comments: Possibly tachytictic (short-term brooder). Little is known about the life history of the Chipola slabshell. A unionine, it is suspected that this species expels conglutinates and is a tachytictic summer releaser. Southeastern congeners of the Chipola slabshell have been documented to use centrarchids (sunfishes) as host fish, although a relationship between cyprinids and tachytictic brooders has been documented (Bruenderman and Neves, 1993). Little else known (Butler and Alam, 1999; USFWS, 2003) and the host fish has not been determined.
Ecology Comments: Apparently intolerant of conditions in Dead Lake and the larger waters of lower Chipola River.
Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: Adults are essentially sessile. About the only voluntary movement they make is to burrow deeper into the substrate although some passive movement downstream may occur during high flows. Dispersal occurs while the glochidia are encysted on their host (probably a fish).
Riverine Habitat(s): CREEK, Low gradient, MEDIUM RIVER, Moderate gradient, Riffle
Special Habitat Factors: Benthic
Habitat Comments: This species is found in muddy sand in moderate current (Heard, 1979). Medium-sized creeks to small rivers in silty sand with slow to moderate current (Williams and Butler, 1994; Williams et al., 1993). Juveniles may require sand and silt-free riffles. The Chipola slabshell inhabits silty sand substrates of large creeks and the main channel of the Chipola River in slow to moderate current (Williams and Butler, 1994). Specimens are generally found in sloping bank habitats. Nearly 70 percent of the specimens found during the status survey were associated with a sandy substrate (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: 8.5 centimeters
Economic Attributes Not yet assessed
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Management Summary
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Stewardship Overview: This species was added to the U.S. federal endangered species list in 1998 as threatened. A recovery plan was created for this species (USFWS, 2003). Critical habitat has been designated for 190.0 km of the Chipola River, Alabama and Florida (USFWS, 2006).
Biological Research Needs: Determine fish hosts of glochidia and reproduction frequency per year of adults; study life history and status of fish-host population(s).
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: 09Jan2014
NatureServe Conservation Status Factors Author: Jackson, D. R. (2014); Cordeiro, J. (2009)
Element Ecology & Life History Edition Date: 17Oct2006
Element Ecology & Life History Author(s): Cordeiro, J.

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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  • 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.

  • Bruenderman, S.A. and R.J. Neves. 1993. Life history of the endangered fine-rayed pigtoe, Fusconaia cuneolus (Bivalvia: Unionidae) in the Clinch River, Virginia. American Malacological Bulletin, 10(1): 83-91.

  • Davis, G.M., W.H. Heard, S.L.H. Fuller, and C. Hesterman. 1981. Molecular genetics and speciation in Elliptio and its relationships to other taxa of North American Unionidae (Bivalvia). Biological Journal of the Linnean Society, 15(2): 131-150.

  • Deyrup, M., and R. Franz. 1994. Rare and Endangered Biota of Florida, Volume IV: Invertebrates. University Press of Florida, Gainesville. 798 pp.

  • Fuller, S.L.H. 1974. Chapter 8: Clams and mussels (Mollusca: Bivalvia). Pages 215-273 in: C.W. Hart, Jr. and S.L.H. Fuller (eds.) Pollution Ecology of Freshwater Invertebrates. Academic Press: New York. 389 pp.

  • Heard, W.H. 1979. Identification manual of the fresh water clams of Florida. State of Florida, Department of Environmental Regulation, Technical Series, 4(2): 1-82.

  • Howard, A.D. 1915. Some exceptional cases of breeding among the Unionidae. The Nautilus 29:4-11.

  • Johnson, R.I. 1970a. The systematics and zoogeography of the Unionidae (Mollusca: Bivalvia) of the southern Atlantic slope region. Bulletin of the Museum of Comparative Zoology, Harvard University 140(6):263-449.

  • Kat, P. and G.M. Davis. 1984. Molecular genetics of peripheral populations of Nova Scotian Unionidae (Mollusca: Bivalva). Biological Journal of the Linnean Society, 22: 157-185.

  • Lefevre, G. and W.T. Curtis. 1912. Studies on the reproduction and artificial propogation of fresh-water mussels. Bulletin of the Bureau of Fisheries 30:102-201.

  • Moyle, P. and J. Bacon. 1969. Distribution and abundance of molluscs in a fresh water environment. Journal of the Minnesota Academy of Science 35(2/3):82-85.

  • Strayer, D. 1983. The effects of surface geology and stream size on freshwater mussel (Bivalvia, Unionidae) distribution in southeastern Michigan, U.S.A. Freshwater Biology 13:253-264.

  • 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.

  • 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.

  • U.S. Fish and Wildlife Service (USFWS) (Butler, R.S., J. Ziewitz, S.K. Alam, and H.N. Blalock-Herod). 2003. Agency draft recovery plan for endangered fat threeridge (Amblema neislerii), shinyrayed pocketbook (Lampsilis subangulata), gulf moccasinshell (Medionidus penicillatus), ochlockonee moccasinshell (Medionidus simpsonianus), oval pigtoe (Pleurobema pyriforme) and threatened chipola slabshell (Elliptio chipolaensis), and purple bankclimber (Elliptoideus sloatianus). United States Fish and Widllife Service, Atlanta, Georgia. 144 pp.

  • U.S. Fish and Wildlife Service (USFWS). 1998. Determination of Endangered Status for five freshwater mussels and Threatened status for two freshwater mussels from the eastern Gulf Slope drainages of Alabama, Florida, and Georgia. Final Rule. Federal Register, 63(50): 12664-12687.

  • U.S. Fish and Wildlife Service (USFWS). 1999. Technical/agency draft recovery plan for endangered fat threeridge (Amblema neislerii), shinyrayed pocketbook (Lampsilis subangulata), gulf moccasinshell (Medionidus penicillatus), ochlockonee moccasinshell (Medionidus penicillatus), oval pigtoe (Pleurobema pyriforme), and purple bankclimber (Elliptoideus sloatianus) and threatened chipola slabshell (Elliptio chipolaensis), and purple bankclimber (Elliptoideus sloatianus). U.S. Fish and Wildlife Service: Atlanta, Georgia. 106 pp.

  • U.S. Fish and Wildlife Service (USFWS). 2006. Endangered and Threatned Wildlife and Plants; Critical Habitat for five endangered and two threatened mussels in four northeast Gulf of Mexico drainages; proposed rule. Federal Register, 71(108): 32746-32795.

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

  • 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., 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, Alabama. 908 pp.

  • Williams, J. D., R. S. Butler, G. L. Warren, and N. A. Johnson.  2014.  Freshwater Mussels of Florida.  University of Alabama Press, Tuscaloosa.  498 pp.

  • Williams, J. D., R. S. Butler, G. L. Warren, and N. A. Johnson.  2014a.  Freshwater Mussels of Florida.  University of Alabama Press, Tuscaloosa, Alabama. 498 pp.

  • Williams, J.D. and R.S. Butler. 1994. Class Bivalvia, Order Unionoida, freshwater bivalves. Pages 53-128, 740-742 in M. Deyrup and R. Frantz (eds.) Rare and Endangered Biota of Florida. Volume 4. Invertebrates. University Press of Florida, Gainesville, Florida. 798 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. 1938b. Contributing factors in the depletion of naiades in eastern United States. Basteria 3(4): 51-57.

  • 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).

  • 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.

  • U.S. Fish and Wildlife Service (USFWS). 2003. Recovery plan for endangered fat threeridge (Amblema neislerii), shinyrayed pocketbook (Lampsilis subangulata), gulf moccasinshell (Medionidus penicillatus), Ochlockonee moccasinshell (Medionidus simpsonianus), and oval pigtoe (Pleurobema pyriforme); and threatened chipola slapshell (Elliptio chipolaensis), and purple bankclimber (Elliptoideus sloatianus). U.S. Fish and Wildlife Service, Atlanta, Georgia. 142 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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