Venustaconcha ellipsiformis - (Conrad, 1836)
Ellipse
Synonym(s): Venustaconcha ellipsiformis ellipsiformis (Conrad, 1836)
Taxonomic Status: Accepted
Related ITIS Name(s): Actinonaias ellipsiformis Conrad (TSN 80191) ;Venustaconcha ellipsiformis (Conrad, 1836) (TSN 80295)
Unique Identifier: ELEMENT_GLOBAL.2.118367
Element Code: IMBIVA4010
Informal Taxonomy: Animals, Invertebrates - Mollusks - Freshwater Mussels
 
Kingdom Phylum Class Order Family Genus
Animalia Mollusca Bivalvia Unionoida Unionidae Venustaconcha
Check this box to expand all report sections:
Concept Reference
Help
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: Venustaconcha ellipsiformis
Taxonomic Comments: The ellipse has been treated as three separate species (Ortmann, 1918) or as one species with two subspecies (Oesch, 1984; 1995). Today, two species are recognized (Turgeon et al., 1998), the ellipse, Venustaconcha ellipsiformis (Conrad, 1836) in the upper Midwest south through the Ozarks and the bleedingtooth mussel, Venustaconcha pleasii (Marsh, 1891) limited to the White River basin of the Ozarks (Riusech, 1999; Barnhart, 2001). Recent pylogenetic analysis of the subfamily Ambleminae confirms Venustaconcha ellipsiformis is a member of the Tribe Lampsilini, but it did not group closely with species with similar mantle flap morphology such as Lampsilis cardium, Lampsilis higginsii, Lampsilis siliquoidea, and Ligumia recta (Campbell et al., 2005; Allen et al., 2007). It appears to be closely related to Ptychobrancus fasciolaris, a species that uses conglutinates, not mantle lures, to attract fish hosts (Watters, 1999), although this relationship is not highly supported (Campbell et al., 1999). It was formerly placed in the genera Unio, Lampsilis, Nephronaias, Eurynia, Ligumia, and Actinonaias.
Conservation Status
Help

NatureServe Status

Global Status: G4
Global Status Last Reviewed: 23Dec2011
Global Status Last Changed: 07Feb2007
Rounded Global Status: G4 - Apparently Secure
Reasons: This is a northern range species in North America that is generally stable except for some edge of range declines to extirpation in Minnesota, Illinois, and Ohio.
Nation: United States
National Status: N4 (07Feb2007)

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 Arkansas (S1), Illinois (S3), Indiana (S2), Iowa (S2), Kansas (S1), Michigan (S3), Minnesota (S2), Missouri (S4), Ohio (SX), Oklahoma (S4?), Wisconsin (S3)

Other Statuses

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

NatureServe Global Conservation Status Factors

Range Extent: 20,000-200,000 square km (about 8000-80,000 square miles)
Range Extent Comments: This northern species has a range extending from Indiana and Michigan to southeastern Minnesota, Iowa, southeastern Kansas, Missouri, Oklahoma (questionable), Arkansas and Kentucky, and has apparently been extirpated from Ohio. Van der Schalie and van der Schalie (1963) had expressed concern that it might be endangered in Michigan, but Hoeh (pers. comm.) stated that his field experience suggested that it may be faring well. Out of 28 stations recently surveyed along the Tittabawassee River of Michigan, a tributary to the Saginaw, the species was present at 16 and abundant at eight stations (Hoeh, pers. comm.). Currently, the species is found at 11 sites in five southeastern Wisconsin river systems. It also occurs in the Fox River drainage in the southwestern part of the state. (K.S. Cummings pers. obs.; Mathiak, 1979). In Kansas, range is restricted to the Spring River in the southeastern corner of the state and the mussel is considered a peripheral species (Busby, pers. comm.; Couch, 1997). In Missouri, range formerly covered areas north of the Missouri River. Current range is the streams that flow north off the Salem and Springfield Plateaus (Oesch, 1984; 1995). The first record from Minnesota was from the Cannon River in 1987 (Davis, 1987). Within the Cannon River watershed, extant populations were discovered in the Straight River, Wolf Creek and the Cannon River proper. The largest population was found within the tailwaters of an old mill dam on the Straight River (Davis, 1987) and although recent survey efforts did not discover this species there (Swift and Wagenbach, 1999), Hove et al. (2005) found 2 live and 3 dead shells in June 2005. Although presently limited in distribution within the drainage, past distribution appears to have been much wider. Subsequent to the Cannon River survey, sites have been found in other river systems within the southeastern corner of the state, the Zumbro (Bright, pers. comm.) and tributaries to the Root (Ostlie, pers. obs.). Allen et al. (2007) compiled data from 1800 sample sites across all of Minnesota (almost 500 from the St. Croix drainage and drainages in southeastern Minnesota) and found the species in 219 sites in five primary tributaries to the Mississippi River: the Cannon, Cedar, Root, Upper Iowa, and Zumbro River systems; with no relic shells in any other systems. Allen et al. (2007) also discounted other records from outside these areas including specimens from the St. Croix River proper (see Graf, 1997). In Iowa, range is the upper reaches of rivers in the northeastern third of Iowa (Frest, pers. comm.; Howell, pers. comm.). Although some records are available from large rivers (judging from recent records of this species from the Mississippi River at Davenport, Muscatine, Prairie du Chien and Keokuk, Frest, pers. comm.) it is rarely found in large river habitats. There have been no records in the state of Ohio (Hoggarth, pers. comm.). Sterki (1907) recorded the species from the Ohio River, but that record did not come from the Ohio portion of the river (Hoggarth, pers. comm.). Although some records also exist in Lake Erie tributaries, none of these are from Ohio. The ellipse was historically found in the northern half of Illinois, particularly in the northeast. However, many streams in that part of Illinois have been negatively effected by urban development and agricultural impacts and many populations have been extirpated. The ellipse is now relatively uncommon in Illinois. A few apparently healthy populations can still be found in tributaries to the Kankakee, Fox, Mackinaw, and Vermilion (Illinois River drainage) rivers. This mussel is rare in Indiana occurring only at a few sites primarily in streams draining into Lake Michigan. A few historical records exist for glacial lakes in the headwaters of the Tippecanoe River (K.S. Cummings pers. obs.).

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

Number of Occurrences: 81 - 300
Number of Occurrences Comments: Reported from Root River system, Minnesota (Havlik, 1995). Also in Minnesota, this species is widespread in southeastern streams where it is locally common to abundant but extremely rare in the Mississippi River below St. Anthony Falls and likely extirpated from the Minnesota River drainage (Sietman, 2003). In Illinois, it is restricted to clear-flowing gravel-bottomed streams in the northern half of the state where it is occasionally found in small numbers (Cummings and Mayer, 1997); including Sangamon, Kankakee, and Mackinaw Rivers (Schanzle and Cummings, 1991) and Aux Sable, DuPage, and Vermillion (Sietman et al., 2001). In Wisconsin, Mathiak (1979) reported it from 11 sites in a row from Walworth to Manitowoc Cos. and other areas in the southern part of the state. It was recently documented in the Fox River basin in Illinois and Wisconsin; where it was not uncommon (typically in headwater areas) (Schanzle et al., 2004). Records from Kansas (Spring River, Marmaton River in Bourbon Co.) (Couch, 1997) are questionable, at best. Relic shells have been documented nearby in the Marais des Cygnes River in Bates Co., Missouri (Couch, 1997). In Missouri it is known to be fairly common from the central prairie region (Oesch, 1995). Allen et al. (2007) compiled data from 1794 sample sites across Minnesota (496 from the St. Croix drainage and drainages in southeastern Minnesota) and found a total of 446 live Venustaconcha ellipsiformis from 219 sites in five primary tributaries to the Mississippi River: the Cannon, Cedar, Root, Upper Iowa, and Zumbro River systems; with no relic shells in any other systems. In Michigan, it was recently collected from the Grand and Red Cedar Rivers (SE Lake Michigan drainage) (Badra and Goforth, 2003).

Population Size: >1,000,000 individuals
Population Size Comments: Allen et al. (2007) compiled data from 1794 sample sites in Minnesota (496 from the St. croix drainage and drainages in southeastern Minnesota) and found a total of 446 live Venustaconcha ellipsiformis from 219 sites in five primary tributaries to the Mississippi River: the Cannon, Cedar, Root, Upper Iowa, and Zumbro River systems; with no relic shells in any other systems.

Number of Occurrences with Good Viability/Integrity: Some to many (13-125)
Viability/Integrity Comments: Also in Minnesota, this species is widespread in southeastern streams where it is locally common to abundant (Sietman, 2003). This is the most abundant mussel species in the Root River drainage (rel. abundance 20.9%) in Minnesota with presence of juveniles and is ranked 6th, 6th, 6th, and 11th in relative abundance in the Zumbro, Cannon, Upper Iowa, and Cedar River drainages, respectively (Allen et al., 2007).

Overall Threat Impact: High
Overall Threat Impact Comments: Smith (1971) ranked the causes of extirpation or declines in fish species as follows: siltation, drainage of bottomland lakes, swamps, and prairie marshes, desiccation during drought, species introductions, pollution, impoundments, and increased water temperatures. All of these factors render habitats unsuitable, cause extirpations, and lead to the isolation of populations thereby increasing their vulnerability to extirpation for many aquatic species (including mussels) throughout North America. Zebra mussels Dreissena polymorpha have destroyed mussel populations in the Great Lakes and significantly reduced mussels in many of the large rivers of the eastern North America and has the potential to severely threaten and other populations especially if it makes its way into smaller streams. Pollution through point (industrial and residential discharge) and non-point (siltation, herbicide and fertilizer run-off) sources is perhaps the greatest on-going threat to this species and most freshwater mussels. The ellipse may be especially hard hit by siltation since it frequents small stream and headwaters (Hoeh, pers. comm.). Lowered dissolved oxygen content and elevated ammonia levels (frequently associated with agricultural runoff and sewage discharge) have been shown to be lethal to some species of freshwater naiads (Horne and McIntosh, 1979). Residential, mineral and industrial development, particulary along the Spring River in Missouri pose a significant threat to this species in Kansas (Busby, pers. comm.). Destruction of habitat through stream channelization and maintenance and the construction of dams although slowed in recent years is still a threat in some areas. Impoundments reduce currents that are necessary for the most basic physiological activities such as feeding, waste removal and reproduction. In addition, reduced water flow typically results in a reduction in water oxygen levels and a settling out of suspended solids (silt, etc.), both of which are detrimental. Dredging of streams has an immediate effect on existing populations by physically removing and destroying individuals. Dredging also affects the long-term recolonization abilities by destroying much of the potential habitat, making the substrates and flow rates uniform throughout the system. Van der Schalie and van der Schalie (1963) expressed concern over the small number of juvenile individuals with respect to other age classes at a particular site. They attributed this situation to destruction of preferential habitat caused by power dam construction, pollution and siltation. Rotenone, a toxin used to kill fish in bodies of water for increased sport fishery quality, has been shown to be lethal to mussels as well (Heard, 1970). Natural predators include raccoons, otter, mink, muskrats, turtles and some birds, which feed heavily upon freshwater mussels (Simpson 1899; Boepple and Coker 1912; Evermann and Clark 1918; Coker, et al. 1921; Parmalee 1967; Snyder and Snyder 1969). Domestic animals such as hogs can root mussel beds to pieces (Meek and Clark 1912). Fishes, particularly catfish, Itcalurus spp. and Amieurus spp. and freshwater drum, Aplodinotus grunniens also consume large numbers of unionids. Intensive agriculture practices are thought to have caused demise of the ellipse throughout its historic range in the southern half of Wisconsin. In Iowa, historical records show that the species may have inhabited much of the state in presettlement times, but siltation and pollution have eliminated the species from much of its former range.

Short-term Trend: Relatively Stable (<=10% change)
Short-term Trend Comments: This species is likely extirpated from the Minnesota River drainage (Sietman, 2003). Mississippi River drainages in Minnesota are well studied and continue to support this species in five drainage basins (Allen et al., 2007). Recently only relict shells found in the Kyte River (Rock basin) in Illinois (Tiemann et al., 2005).

Long-term Trend: Decline of <30% to increase of 25%
Long-term Trend Comments: It is questionable whether this species ever occurred in Ohio (it occurs just a few miles north in Michigan in the St. Joseph system), and there is no documentation of any occurrences in teh state despite the proximity in Michigan just 30km away (Watters, 1995; Watters et al., 2009).

Intrinsic Vulnerability: Moderately vulnerable
Intrinsic Vulnerability Comments: Behaviors reported for most suitable host species suggest these fishes may not enter large channelized rivers and move into other watersheds during the period of glochidial encystment, suggesting Venustaconcha ellipsiformis has a relatively low dispersal rate (Allen et al., 2007). Allen et al. (2007) suggest sub-populations are more isolated than mussel species whose hosts can disperse juvenile mussels more rapidly and broadly.

Environmental Specificity: Narrow. Specialist or community with key requirements common.

Other NatureServe Conservation Status Information

Inventory Needs: Status surveys are needed in Iowa, Indiana, and Arkansas and other states that have not been sampled in recent years.

Protection Needs: Since this species appears to be a small stream species, it might be possible to protect some of the better sites.

Distribution
Help
Global Range: (20,000-200,000 square km (about 8000-80,000 square miles)) This northern species has a range extending from Indiana and Michigan to southeastern Minnesota, Iowa, southeastern Kansas, Missouri, Oklahoma (questionable), Arkansas and Kentucky, and has apparently been extirpated from Ohio. Van der Schalie and van der Schalie (1963) had expressed concern that it might be endangered in Michigan, but Hoeh (pers. comm.) stated that his field experience suggested that it may be faring well. Out of 28 stations recently surveyed along the Tittabawassee River of Michigan, a tributary to the Saginaw, the species was present at 16 and abundant at eight stations (Hoeh, pers. comm.). Currently, the species is found at 11 sites in five southeastern Wisconsin river systems. It also occurs in the Fox River drainage in the southwestern part of the state. (K.S. Cummings pers. obs.; Mathiak, 1979). In Kansas, range is restricted to the Spring River in the southeastern corner of the state and the mussel is considered a peripheral species (Busby, pers. comm.; Couch, 1997). In Missouri, range formerly covered areas north of the Missouri River. Current range is the streams that flow north off the Salem and Springfield Plateaus (Oesch, 1984; 1995). The first record from Minnesota was from the Cannon River in 1987 (Davis, 1987). Within the Cannon River watershed, extant populations were discovered in the Straight River, Wolf Creek and the Cannon River proper. The largest population was found within the tailwaters of an old mill dam on the Straight River (Davis, 1987) and although recent survey efforts did not discover this species there (Swift and Wagenbach, 1999), Hove et al. (2005) found 2 live and 3 dead shells in June 2005. Although presently limited in distribution within the drainage, past distribution appears to have been much wider. Subsequent to the Cannon River survey, sites have been found in other river systems within the southeastern corner of the state, the Zumbro (Bright, pers. comm.) and tributaries to the Root (Ostlie, pers. obs.). Allen et al. (2007) compiled data from 1800 sample sites across all of Minnesota (almost 500 from the St. Croix drainage and drainages in southeastern Minnesota) and found the species in 219 sites in five primary tributaries to the Mississippi River: the Cannon, Cedar, Root, Upper Iowa, and Zumbro River systems; with no relic shells in any other systems. Allen et al. (2007) also discounted other records from outside these areas including specimens from the St. Croix River proper (see Graf, 1997). In Iowa, range is the upper reaches of rivers in the northeastern third of Iowa (Frest, pers. comm.; Howell, pers. comm.). Although some records are available from large rivers (judging from recent records of this species from the Mississippi River at Davenport, Muscatine, Prairie du Chien and Keokuk, Frest, pers. comm.) it is rarely found in large river habitats. There have been no records in the state of Ohio (Hoggarth, pers. comm.). Sterki (1907) recorded the species from the Ohio River, but that record did not come from the Ohio portion of the river (Hoggarth, pers. comm.). Although some records also exist in Lake Erie tributaries, none of these are from Ohio. The ellipse was historically found in the northern half of Illinois, particularly in the northeast. However, many streams in that part of Illinois have been negatively effected by urban development and agricultural impacts and many populations have been extirpated. The ellipse is now relatively uncommon in Illinois. A few apparently healthy populations can still be found in tributaries to the Kankakee, Fox, Mackinaw, and Vermilion (Illinois River drainage) rivers. This mussel is rare in Indiana occurring only at a few sites primarily in streams draining into Lake Michigan. A few historical records exist for glacial lakes in the headwaters of the Tippecanoe River (K.S. Cummings pers. obs.).

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 AR, IA, IL, IN, KS, MI, MN, MO, OHextirpated, OK, WI

Range Map
No map available.


U.S. Distribution by County Help
State County Name (FIPS Code)
AR Benton (05007), Crawford (05033), Fulton (05049), Washington (05143)
IA Benton (19011), Bremer (19017), Buchanan (19019), Cerro Gordo (19033), Chickasaw (19037), Delaware (19055), Dubuque (19061), Fayette (19065)*, Floyd (19067), Howard (19089), Jackson (19097), Jones (19105), Linn (19113), Mitchell (19131), Winneshiek (19191)
IN Benton (18007), Elkhart (18039), Hamilton (18057), Hancock (18059), Lagrange (18087), Lake (18089), Marion (18097), Miami (18103), Noble (18113), Porter (18127), Steuben (18151)
KS Cherokee (20021)
MI Allegan (26005), Barry (26015), Berrien (26021), Branch (26023)*, Calhoun (26025), Cass (26027)*, Clinton (26037), Eaton (26045), Genesee (26049)*, Gladwin (26051)*, Gratiot (26057), Hillsdale (26059), Ingham (26065), Ionia (26067), Isabella (26073), Jackson (26075), Kalamazoo (26077), Kent (26081), Leelanau (26089), Livingston (26093)*, Mecosta (26107), Midland (26111), Montcalm (26117), Muskegon (26121)*, Ogemaw (26129)*, Saginaw (26145), Shiawassee (26155), St. Joseph (26149), Tuscola (26157), Van Buren (26159), Washtenaw (26161)
MN Blue Earth (27013), Chippewa (27023), Dakota (27037), Dodge (27039), Fillmore (27045), Goodhue (27049), Mower (27099), Olmsted (27109), Renville (27129), Rice (27131), Steele (27147), Wabasha (27157), Washington (27163), Yellow Medicine (27173)
WI Chippewa (55017), Dane (55025), Dodge (55027), Fond Du Lac (55039), Grant (55043), Jefferson (55055), Kenosha (55059)*, Lafayette (55065), Manitowoc (55071), Ozaukee (55089), Racine (55101)*, Rock (55105), Sheboygan (55117), Taylor (55119), Walworth (55127), Washington (55131), Waukesha (55133)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
04 Manitowoc-Sheboygan (04030101)+, Little Calumet-Galien (04040001)+, Milwaukee (04040003)+, St. Joseph (04050001)+, Kalamazoo (04050003)+, Upper Grand (04050004)+, Maple (04050005)+, Lower Grand (04050006)+, Thornapple (04050007)+, Muskegon (04060102)+*, Betsie-Platte (04060104)+, Tittabawassee (04080201)+, Pine (04080202)+, Shiawassee (04080203)+, Cass (04080205)+, Raisin (04100002)+, St. Joseph (04100003)+
05 Eel (05120104)+, Upper White (05120201)+, Driftwood (05120204)+
07 Twin Cities (07010206)+, Hawk-Yellow Medicine (07020004)+, Blue Earth (07020009)+, Cannon (07040002)+, Zumbro (07040004)+, Root (07040008)+, Lower Chippewa (07050005)+, Upper Iowa (07060002)+, Grant-Little Maquoketa (07060003)+, Turkey (07060004)+, Maquoketa (07060006)+, Upper Wapsipinicon (07080102)+, Lower Wapsipinicon (07080103)+, Upper Cedar (07080201)+, Shell Rock (07080202)+, Winnebago (07080203)+, Middle Cedar (07080205)+, Upper Rock (07090001)+, Crawfish (07090002)+, Pecatonica (07090003)+, Sugar (07090004)+, Iroquois (07120002)+, Upper Fox (07120006)+
11 Spring (11010010)+, Spring (11070207)+, Illinois (11110103)+, Robert S. Kerr Reservoir (11110104)+
+ 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
Help
Basic Description: A freshwater mussel, small, relatively think shell, elliptical in shape, greenish-brown in color with wavy green rays on the posterior end.
General Description: A description from Oesch (1984) follows: SHELL: "Shell elliptic, oblong, solid; dorsal margin slightly curved, ventral margin gently curved, anterior end uniformly rounded, posterior end sharply rounded. Anterior half of the valve noticeably thicker than the posterior half in older shells; size to 7 cm; compressed to moderately inflated; posterior ridge broadly rounded and flattened posteriorly. Beaks only slightly raised above the hinge line; inequipartite; sculpture, which is seldom seen due to erosion on the beaks, consists of three or four concentric ridges drawn up in the middle. Epidermis yellow-brown changing to brown in older shells; green rays usually cover most of the shell; on posterior slope the rays are thin and wavy."

"Left valve has two thick, triangular, roughened, divergent pseudocardinal teeth; the lateral teeth are short, thick and finely striated. Right valve has a single thick, triangular pseudocardinal tooth; usually there is a small lamellar denticle anteriorly; lateral tooth short, finely striated. Interdentum absent to moderately wide; beak cavity shallow; nacre bluish- white in the center and often tinged with a rusty salmon color; all teeth are usually a rusty-red color, iridescent posteriorly".

NUTRITIVE STRUCTURES: "Branchial opening with numerous yellowish papillae; anal very finely papillose; supra-anal small, high, closely but distinctly connected to anal; gills large, pointed even in the marsupial ones; inner laminae of inner gills connected entirely to visceral mass; palpi sickle- shaped; color of soft parts the usual dirty white with posterior mantle edges blackened".

REPRODUCTIVE STRUCTURES: "Marsupium occupying posterior half of outer gills, consisting of about 20 ovisacs separated by thick septa, when gravid extending below the original edge of sterile marsupium, tips pigmented with bluish, beaded spots; mantle edge antero-ventrad to branchial opening with papillae terminating in rather fine crenulations centrad-ventrad; conglutinates and glochidia unknown".

Reproduction Comments: Gonads apparently remain in an undeveloped state until individuals are three years old, at which time the individuals can be sexed. During breeding periods, individuals will become mobile, sometimes forming relatively dense congregations of the species.

This mussel has a long-term breeding cycle in which the gills become gravid in the late summer and early fall and the glochidia are shed in late spring or early summer (van der Schalie and van der Schalie, 1963). Apparently, it is not unusual for some individuals to come gravid while other individuals have not shed their glochidia from the previous year. Hove and Kurth (1998) found that Cottus cognatus (slimy sculpins), Culaea inconstans (brook stickleback), Etheostoma exile (Iowa darter), Etheostoma flabellare (fantail darter), Percina caprodes (logperch), Percina maculata (blackside darter), and Etheostoma nigrum (Johnny darters) could serve as suitable glochidial hosts. Earlier studies by Hillgrass and Hove (1997) found Percina maculata (blackside darter) to be a suitable glochidial host but in this study only three juveniles metamorphosed on this fish. Hove and Anderson (1997) found Cottus cognatus (slimy sculpin), Etheostoma nigrum (Johnny darter) to be suitable hosts.

While the glochidia of the previous year are still carried in the ovisacs of the outer, posterior gills of the females, the gonads contain many eggs in the early stages of development (van der Schalie and van der Schalie, 1963). By the end of July, most of the unfertilized eggs have moved to the gills where they are fertilized and carried into the following spring or summer. In August, the gonads again show numerous eggs in the early stages of development.

The glochidia of Venustaconcha ellipsiformis are apparently very similar to those produced by Actinonaias carinata. Van der Schalie and van der Schalie, (1963) found that the average size of V. ellipsiformis glochidia in Michigan was 0.237 mm by 0.285 mm. Even though adult individuals of V. ellipsiformis are significantly smaller than adults of A. carinata, the glochidia are larger. In comparison, A. carinata glochidia average 0.220 mm by 0.260 mm (Surber, 1912).

The gills become highly modified when gravid so that it is relatively easy to count the number of ovisacs present in the posterior portion of the outer gills (van der Schalie and van der Schalie, 1963). The number of ovisacs present is directly proportional to the size of the individual. An individual 32 mm in length possesses on average 9 ovisacs per gill, while individuals 55 mm in length possess 25 ovisacs per gill. The average of 20 ovisacs per gill given by Baker (1928) is apparently the average for females that are 5 years or more in age and are between 45 and 52 mm in length (van der Schalie and van der Schalie, 1963).

In males, spermatogenesis occurs during all months of the year. During the active and growing season, mature sperm are shed from mid-May to July. In addition, sperm develop throughout the fall and winter months and are apparently shed in late spring and early summer (April and May) (van der Schalie and van der Schalie, 1963).

Hermaphroditism is apparently extremely rare in this species. Of 218 live specimens collected by van der Schalie and van der Schalie (1963), only one was hermaphroditic.

Brooding individuals quickly flap a small mantle extension, often in response to passing shadows or jarring of the substrate, or their mantle extensions may be slowly undulated when observed in the wild (Allen et al., 2007).

Hosts listed in Hove and Kapuscinski (1998) include: Cottus inconstans (brook stickleback), Etheostoma exile (Iowa darter), Etheostoma flabellare (fantail darter), Percina maculata (blackside darter) with juveniles metamorphosing on Percina caprodes (logperch) and Cottus bairdi (mottled sculpin) but not surviving to completion of the study. Barnhart and Riusech (2000) list Etheostoma spectabile (orangethroat darter), Etheostoma caeruleum (rainbow darter), Etheostoma blennioides (greenside darter), Etheostoma whipplei (redfin darter), Luxilus cardinalis (cardinal shiner), and Etheostoma juliae (yoke darter) to be suitable hosts. In addition, Allen et al. (2007) identified or reconfirmed the following hosts: Cottus bairdii, Cottus cognatus, Culaea inconstans, Etheostoma aspigene, Etheostoma caeruleum, Etheostoma exile, Etheostoma flabellare, Etheostoma nigrum, Etheostoma zonale, Percina caprodes, and Percina maculata.

Ecology Comments: Associates in Iowa include ANODONTA GRANDIS, ANADONTOIDES FERUSSACIANUS, STROPHITUS UNDULATUS, LASMIGONA COMPLANATA, LASMIGONA COMPRESSA, AMBLEMA PLICATA, LAMPSILIS SILIQUOIDEA and L. VENTRICOSA (Howell, pers. comm.). Associates at a site on the Kalamazoo River included ELLIPTIO DILATATA, LASMIGONA COSTATA and ALASMIDONTA MARGINATA (Hoggarth, pers. comm.).

This mussel spends most of its life buried (except for the posterior third) in the substrate of the aquatic habitats in which it lives (Frest, pers. comm.).

Habitat Type: Freshwater
Non-Migrant: N
Locally Migrant: N
Long Distance Migrant: N
Riverine Habitat(s): CREEK, MEDIUM RIVER, Riffle
Special Habitat Factors: Benthic
Habitat Comments: In Illinois this species is found in clear, small to medium-sized streams in gravel or mixed sand and gravel, in riffles or runs with a swift to moderate current. Rarely found in mud. Very rare in large rivers (Cummings and Mayer, 1992). In Michigan, preferred habitat is small, clear streams that possess a gravel, rocky substrate (Hoeh, pers. comm.; Hoggarth, pers. comm; van der Schalie and van der Schalie, 1963). In these small streams the mussel appears to be restricted to areas with moderate or strong currents (van der Schalie and van der Schalie, 1963). Kansas habitat is one Ozark stream that flows through agricultural land and forests. The mussel occupies diverse aquatic habitats, including pools, riffles, runs and backwaters. The substrate is variable, ranging from bedrock to rubble, gravel and silt (Busby, pers. comm.). In Missouri, habitat is small to medium-sized streams that have a gravel substrate (Oesch, 1984). All specimens located during the Cannon River, Minnesota survey were found in pool habitats, either due to preference toward this habitat or displacement by floodwaters into it (Davis, 1987). In other southern Minnesota rivers habitat is clear headwater areas with substrates of gravel, cobbles and boulders (Bright, pers. comm.). Preferred habitat in Iowa is substrates that are typically composed of mixed sand and gravel (Frest, pers. comm.; Howell, pers. comm.). The mussel is able to live in river lakes, but is generally absent from kettle lakes. It can be found occasionally in kettle lakes that are large and possess sand bottoms, however (Frest, pers. comm.). Allen et al. (2007) compiled data from 1794 sample sites in Minnesota (496 from the St. Croix drainage and drainages in southeastern Minnesota) and found a total of 446 live Venustaconcha ellipsiformis from 219 sites all but one of which was found in medium-sized tributaries ans smaller streams.
Food Comments: See the General Freshwater Mussel ESA.
Economic Attributes Not yet assessed
Help
Management Summary
Help
Stewardship Overview: Monitoring needs include the tracking of water quality at selected sites, including measurements of turbidity and pollution levels. Periodic censuses of representative populations should also be made. Research should be centered around the identification of the fish host, determination of the true status and distribution, and the ecological requirements necessary for survival. Management must be centered around the maintenance and enhancement of water quality in existing systems.
Restoration Potential: The specific recovery potential is unknown at this time. However, there is optimism that the species will be able to multiply in areas if water and habitat quality is increased and the host fish is (are) present. In areas where stream modification has taken place (channelization and impoundment), recovery of historical populations may be impossible without a large-scale, long-term effort.
Preserve Selection & Design Considerations: In order to adequately protect a population within a given watershed, all activities influencing the river must be taken into account. Attempts must be made to reduce the amounts of agricultural run-off (pesticides, silt, etc.). Broad buffer zones along rivers, contour farming, soil erosion control programs, and reductions in pesticide use should all be considered as methodologies to alleviate existing problems in agricultural areas. In other areas, reduced water quality through clear-cut logging practices may need special attention.

Further construction of stream and river impoundments should be eliminated. Loss of mussel habitat and barriers to fish migration are both significant threats that need to be addressed in any land protection effort.

Management Requirements: Generally, this is a species dependant on clear waters. Stream protection via buffer strips and halting of channelization projects would greatly enhance the potential long-term viability of extant populations (Howell, pers. comm.).

Land use practices within the watershed of the species should be geared to reduce non-point and point-source pollution. Until more research concerning this taxon is conducted, management procedures cannot be determined to the specificity required to guarantee adequate protection.

Monitoring Requirements: Basic monitoring should include measurements of water quality (Busby, pers. comm.), including turbidity, nitrate and other pollution levels, in order to determine whether any of these parameters are influencing current or future population trends.

A periodic census (every five years) should be conducted in order to determine if species distribution has changed in selected stream and river stretches (Howell, pers. comm.), and to acquire basic demographical information. Since this is a fairly common species in portions of its range, this sampling interval should suffice. In any case, this estimate should be used only as a crude guideline. Individual monitoring programs should be altered to meet the needs inherent with each.

Stansbury et al. (1986) have shown that individuals may be removed from the substrate, measured or marked, and returned without harm to the animal. Information should be gathered concerning the demography of the population by counting annual growth rings, although these may be difficult to determine in older living individuals. The period of investigation should coincide with the breeding period, roughly late summer to early fall.

Management Research Needs: To ensure full protection, research must be conducted with regard to fish host determination. Protection of this species requires that it have sufficient protection during all phases of its life cycle. For this species to reproduce in a given year, its host or hosts must be available to it (Hoggarth, pers. comm.).

A detailed literature and stream survey should be conducted throughout the range of the species in order to determine the true status and distribution of the species (Henschen, pers. comm.; Hoggarth, pers. comm; Howell, pers. comm.). At present, we have only a partial record of existing populations based on insufficient survey work. In many areas, information currently being used is at least 25 years old (Hoggarth, pers. comm.).

The precise ecological requirements of the species need to be determined. Research centering on minimum water flow requirements, substrate preferences, influences of water temperature and food quality on growth rates, minimum dissolved oxygen level requirements, etc., needs to undertaken.

Biological Research Needs: In order to effectively manage mussel species it is necessary to work out certain life history characteristics first. Because of their unusual life-cycle and dependence on fish for completion of that cycle, it is imperative that the host species for the ellipse be ascertained. Although some life history information has been published for the ellipse in Michigan (van der Schalie and van der Schalie 1963), additional work needs to be done to identify age and size at sexual maturity, recruitment success, age class structure, and other important life history parameters. Research is needed to assess the success of watershed protection on mussel populations. Abundance and distribution of selected species needs to be monitored in order to ascertain how species abundanceOs change over time. From that we can assess what land-use changes, conservation practices, and physical/chemical parameters are correlated with, and possibly responsible for, the biological changes.
Population/Occurrence Delineation
Help
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
Help
U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
Help
Authors/Contributors
Help
NatureServe Conservation Status Factors Edition Date: 23Dec2011
NatureServe Conservation Status Factors Author: Cordeiro, J. (2011); Whittaker, J.C.; Ostlie, W.; Cummings, K.S. (1998)
Management Information Edition Date: 01Jun1990
Management Information Edition Author: OSTLIE, WAYNE
Element Ecology & Life History Edition Date: 23Dec2011
Element Ecology & Life History Author(s): Cordeiro, J. (2011); OSTLIE, W. (1991)

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

References
Help
  • Allen, D. C., B. E. Sietman, D. E. Kelner, M. C. Hove, J. E. Kurth, J. M. Davis, J. L. Weiss, and D. J. Hornbach. 2007. Early life-history and conservation status of Venustaconcha ellipsiformis (Bivalvia, Unionidae) in Minnesota. American Midland Naturalist 157:74-91.

  • Allen, D.C., B.E. Sietman, D.E. Kelner, M.C. Hove, J.E. Kurth, J.M. Davis, J.L. Weiss, and D.J. Hornbach. 2007. Early life-history and conservation status of Venustaconcha ellipsiformis (Bivalvia, Unionidae) in Minnesota. American Midland Naturalist, 157: 74-91.

  • Baker, F.C. 1928b. The freshwater Mollusca of Wisconsin: Part II. Pelecypoda. Bulletin of the Wisconsin Geological and Natural History Survey, University of Wisconsin, 70(2): 1-495.

  • Barnhart, C. 2001. Venustaconcha in the Spring River are something special. Kansas Pearly Mussel Newsline, 6(1): 1-2.

  • Boepple, J.F. and R.E. Coker. 1912. Mussel resources of the Holston and Clinch rivers of eastern Tennessee. Bureau of Fisheries Document 765. 13 pp.

  • Bright, R. C., E. Plummer, and D. Olson. 1988. A survey of the mussels of the Zumbro River drainage, southeastern Minnesota. Report submitted to Minnesota Department of Natural Resources. 27 pp. + tables, figures, and appendices.

  • Campbell, D.C., J.M. Serb, J.E. Buhay, K.J. Roe, R.L. Minton, and C. Lydeard. 2005. Phylogeny of North American amblemines (Bivalvia, Unionoida): prodigious polyphyly proves pervasive across genera. Invertebrate Biology, 124(2): 131-164.

  • Coker, R.E., A.F. Shira, H.W. Clark, and A.D. Howard. 1921. Natural history and propagation of fresh-water mussels. Bulletin of the Bureau of Fisheries [Issued separately as U.S. Bureau of Fisheries Document 839] 37(1919-20):77-181 + 17 pls.

  • Couch, K.J. 1997. An Illustrated Guide to the Unionid Mussels of Kansas. Karen J. Couch. [Printed in Olathe, Kansas]. 124 pp.

  • Cummings, K.S. and C.A. Mayer. 1992. Field Guide to Freshwater Mussels of the Midwest. Illinois Natural History Survey Manual 5, Illinois. 194 pp.

  • Davis, M. 1987. Freshwater mussels (Mollusca: Bivalvia: Unionidae) of the Cannon River Drainage in souteastern Minnesota. Report submitted to the Non-Game Wildlife Program. Minnesota Department of Natural Rsources, St. Paul, Minnesota.

  • Davis, M. 1987. Freshwater mussels (Mollusca: Bivalvia: Unionidae) of the Cannon River drainage in southeastern Minnesota. Final report submitted to the Nongame Wildlife Program, Minnesota Department of Natural Resources. 21 pp. + figures and original data sheets.

  • Davis, Mike. 1987. Freshwater Mussels (Mollusca: Bivalvia: Unionidae) of the Cannon River Drainage in Southeastern Minnesota. Funded by the MN DNR, Section of Wildlife, Nongame Research Program. Results in unpublished report.

  • Dawley, C. 1947. Distribution of aquatic mollusks in Minnesota. American Midland Naturalist 38:671-697.

  • Evermann, B.W. and H.W. Clark. 1918. The Unionidae of Lake Maxinkukee. Proceedings of the Indiana Academy of Science 1917:251-285.

  • Graf, D.L. 1997. Distribution of unionoid (Bivalvia) faunas in Minnesota, USA. The Nautilus, 110(2): 45-54.

  • Havlik, M.E. 1995. A 1994 unionid mussel survey (Mollusca: Bivalvia: Unionidae) from the headwaters of the Root River system, MN, to the Mississippi River. Final report to Minnesota Department of Natural Resources, Nongame Research Program, St. Paul, Minnesota, June 1995. 28 pp.

  • Heard, W.H. 1970. Eastern freshwater mollusks. 1. The south Atlantic and Gulf drainages. In: A.H. Clarke (ed.) Rare and endangered molluscs of North America. Malacologia 10:1-56.

  • Hillegass, K.R. and M.C. Hove. 1997. Suitable fish hosts for glochidia of three freshwater mussels: strange floater, ellipse, and snuffbox. Triannual Unionid Report, 13: 25.

  • Horne, F.R. and S. McIntosh. 1979. Factors influencing distribution of mussels in the Blanco River of central Texas. The Nautilus 94(4):119-133.

  • Hove, M. and A.R. Kapuscinski. 1998. Ecological relationships between six rare Minnesota mussels and their host fishes. Final Report to the Minnesota Department of Natural Resources, Natural Heritage and Nongame Research Program, St. Paul, Minnesota. 17 pp.

  • Hove, M., M. Cox, B. Dickinson, E. Evans, E. Kushner, and D. Hornbach. 2005. Mussel diversity downstream of future dam redconstruction site is similar to that observed nearly 20 years ago. Ellipsaria, 7(3): 14-15.

  • Hove, M.C. and T.W. Anderson. 1997. Mantle-waving behavior and suitable fish hosts of the ellipse. Triannual Unionid Report, 11: 3.

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

  • Kelner, D., M. Davis. 2002. Final report: mussel (Bivalvia:Unionidae) survey of the Mississippi National River and Recreation Area Corridor, 2000-01. Final report submitted by the Minnesota Department of Natural Resources. 44 pp. + appendices.

  • 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.

  • Mathiak, H.A. 1979. A river survey of the unionid mussels of Wisconsin, 1973-1977. Sand Shell Press: Horicon, Wisconsin. 75 pp.

  • 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.

  • Natural Resources Commission. 2014. Roster of Indiana Animals, Insects, and Plants That Are Extirpated, Endangered, Threatened or Rare. Information Bulletin #2 (Sixth Amendment. 20pp.

  • Neves, R. J. 1993. A state-of-the-unionids address. Pages 1-10 in K. S. Cummings, A. C. Buchanan, and L. M. Koch, editors. 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.

  • 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.

  • Ortmann, A.E. 1918b. The systematic position of two species of mussels from the Ozarks. The Nautilus 32(1): 13-15.

  • Parmalee, P.W. 1967. The freshwater mussels of Illinois. Illinois State Museum, Popular Science Series 8:1-108.

  • Riusech, F. A., and M. C. Barnhart. 2000. Host suitability and utilization in Venustaconcha ellipsiformis and Venustaconcha pleasii (Bivalvia: Unionidae) from the Ozark Plateaus. Pages 83-91 in R. A. Tankersley, D. I. Warmolts, G. T. Watters, B. J. Armitage, P. D. Johnson, and R. S. Butler, editors. Freshwater Mollusk Symposia Proceedings. Part I. Proceedings of the Conservation, Captive Care and Propagation of Freshwater Mussels Symposium. Ohio Biological Survey Special Publication, Columbus, Ohio.

  • Riusech, F.A. and M.C. Barnhart. 2000. Host suitability and utilization in Venustaconcha ellipsiformis and Venustaconcha pleasii (Bivalvia: Unionidae) from the Ozark plateaus. Pages 83-91 in in R.A. Tankersley, D.I. Warmolts, G.T. Watters, B.J. Armitage, P.D. Johnson, and R.S. Butler (eds.). Freshwater Mollusk Symposia Proceedings. Ohio Biological Survey, Columbus, Ohio. 274 pp.

  • Riusech, F.R. 1999. Genetic and life history characteristics of Venustaconcha ellipsiformis and Venustaconcha pleasii (Bivalvia: Unionidae) in the Ozark Plateau region. M.S. Thesis, Southwest Missouri State University.

  • Schanzle, R.W. and K.S. Cummings. 1991. A survey of the freshwater mussels (Bivalvia: Unionidae) of the Sangamon River basin, Illinois. Illinois Natural History Survey Biological Notes, 137: 1-25.

  • Schanzle, R.W., G.W. Kruse, J.A. Kath, R.A. Klocek, and K.S. Cummings. 2004. The freshwater mussels (Bivalvia: Unionidae) of the Fox River basin, Illinois and Wisconsin. Illinois Natural History Biological Notes, 141: 1-35.

  • Sietman, B. E. 2003. Field guide to the freshwater mussels of Minnesota. Minnesota Department of Natural Resources, St. Paul, Minnesota. 144 pp.

  • Simpson, C.T. 1899. The pearly fresh-water mussels of the United States; their habits, enemies, and diseases, with suggestions for their protection. Bulletin of the U.S. Fish Commission [Issued separately as U.S. Bureau of Fisheries Document 413] 18(1898):279-288.

  • Smith, P.W. 1971. Illinois streams: A classification based on their fishes and an analysis of factors responsible for disappearance of native species. Illinois Natural History Survey Biological Notes 76:1-14.

  • Snyder, N. and H. Snyder. 1969. A comparative study of mollusk predation by Limpkins, Everglade Kites, and Boat-tailed Grackles. Eighth Annual Report of the Cornell Laboratory of Ornithology 8:177-223.

  • Stansbery, D.H., C.B. Stein, and G.T. Watters. 1986. The naiad fauna of the Clinch River in the vicinity of the Clinch River Power Plant at Carbo, Virginia. Final Report submitted to American Electric Power. unpaginated.

  • Sterki, V. 1907. A preliminary catalogue of the land and fresh-water Mollusca of Ohio. Proceedings of the Ohio State Academy of Science, 4(8): 367-402.

  • 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.

  • Surber, T. 1912. Identification of the glochidia of freshwater mussels. Report submitted to U.S. Bureau of Fisheries, document 777: 1-10.

  • Swift, M.C. and G.E. Wagenbach. 1999. A survey of mussel faunas in the Cannon River and Superior National Forest. Final report to the Minnesota Department of Natural Resources, St. Paul, Minnesota. 41 pp.

  • Turgeon, D.D., A.E. Bogan, E.V. Coan, W.K. Emerson, W.G. Lyons, W.L. Pratt, C.F.E. Roper, A. Scheltema, F.G. Thompson, and J.D. Williams. 1988. Common and scientific names of aquatic invertebrates from the United States and Canada: mollusks. American Fisheries Society Special Publication 16: viii + 277 pp., 12 pls.

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

  • Watters, G.T. 1994. An annotated bibliography of the reproduction and propagation of the Unionoidea (primarily of North America). Ohio Biological Survey Miscellaneous Contributions, 1: 1-158.

  • 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.

  • Watters, G.T. 1999. Morphology of the conglutinate of the kidneyshell freshwater mussel, Ptychobranchus fasciolaris. Invertebrate Biology 118(3): 289-295.

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

  • 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.

  • Wilson, C.B. and H.W. Clark. 1912. The mussel fauna of the Kankakee basin. Report and Special Papers of the U.S. Fish Commission [Issued separately as U.S. Bureau of Fisheries Document 758] 1911:1-52 + 1 map.

  • Wisconsin Bureau of Endangered Resources (WI BER). 1990. Endangered and threatened species list undergoes major revision. The Niche: Newsletter of the Wisconsin Bureau of Endangered Resources 4(1):1-11.

  • van der Schalie, H. and A. van der Schalie. 1963. The distribution, ecology, and life history of the mussel, Actinonaias ellipsiformis (Conrad), in Michigan. Occasional Papers of the Museum of Zoology, University of Michigan, 633: 1-17.

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

  • van der Schalie, H., and A. van der Schalie. 1963. The distribution, ecology, and life history of the mussel, Actinonaias ellipsiformis (Conrad), in Michigan. Occasional Papers of the Museum of Zoology, University of Michigan No. 633. 17 pp.

References for Watershed Distribution Map
  • 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.

  • 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.

  • Gordon, M.E. 1982. Mollusca of the White River, Arkansas and Missouri. The Southwestern Naturalist, 27(3): 347-352.

  • Illinois State Museum. 2006. ISM Collections Online: Zoology: Fresh Water Mussel Collection Database. Curatorial Content: Dr. Robert Warren. Online. Available: http://www.museum.state.il.us/ismdepts/zoology/mussels/index.html

  • NatureServe. No Date. Full species reconciliation of subspecies-by-watershed source data for freshwater fish, mussel and crayfish for use in the watershed distribution databases.

  • Oesch, R.D. 1984a. Missouri Naiades: a Guide to the Mussels of Missouri. Jefferson City, Missouri: Conservation Commision of the State of Missouri. 270 pp.

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

  • Sietman, B.E., S.D. Whitney, D.E. Kelner, K.D. Blodgett, and H.L. Dunn. 2001. Post-extirpation recovery of the freshwater mussel (Bivalvia: Unionidae) fauna in the Upper Illinois River. Journal of Freshwater Ecology, 16(2): 273-281.

  • Tiemann, J.S., R.E. Szafoni, and K. Roman. 2005. Freshwater mussel (Bivalvia: Unionidae) survey of Kyte River, Ogle County, Illinois. Transactions of the Illinois State Academy of Science 98(3-4):159-169.

Use Guidelines & Citation

Use Guidelines and Citation

The Small Print: Trademark, Copyright, Citation Guidelines, Restrictions on Use, and Information Disclaimer.

Note: All species and ecological community data presented in NatureServe Explorer at http://explorer.natureserve.org were updated to be current with NatureServe's central databases as of March 2019.
Note: This report was printed on

Trademark Notice: "NatureServe", NatureServe Explorer, The NatureServe logo, and all other names of NatureServe programs referenced herein are trademarks of NatureServe. Any other product or company names mentioned herein are the trademarks of their respective owners.

Copyright Notice: Copyright © 2019 NatureServe, 2511 Richmond (Jefferson Davis) Highway, Suite 930, Arlington, VA 22202, U.S.A. All Rights Reserved. Each document delivered from this server or web site may contain other proprietary notices and copyright information relating to that document. The following citation should be used in any published materials which reference the web site.

Citation for data on website including State Distribution, Watershed, and Reptile Range maps:
NatureServe. 2019. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. NatureServe, Arlington, Virginia. Available http://explorer.natureserve.org. (Accessed:

Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Bird Range Maps of North America:
"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

Restrictions on Use: Permission to use, copy and distribute documents delivered from this server is hereby granted under the following conditions:
  1. The above copyright notice must appear in all copies;
  2. Any use of the documents available from this server must be for informational purposes only and in no instance for commercial purposes;
  3. Some data may be downloaded to files and altered in format for analytical purposes, however the data should still be referenced using the citation above;
  4. No graphics available from this server can be used, copied or distributed separate from the accompanying text. Any rights not expressly granted herein are reserved by NatureServe. Nothing contained herein shall be construed as conferring by implication, estoppel, or otherwise any license or right under any trademark of NatureServe. No trademark owned by NatureServe may be used in advertising or promotion pertaining to the distribution of documents delivered from this server without specific advance permission from NatureServe. Except as expressly provided above, nothing contained herein shall be construed as conferring any license or right under any NatureServe copyright.
Information Warranty Disclaimer: All documents and related graphics provided by this server and any other documents which are referenced by or linked to this server are provided "as is" without warranty as to the currentness, completeness, or accuracy of any specific data. NatureServe hereby disclaims all warranties and conditions with regard to any documents provided by this server or any other documents which are referenced by or linked to this server, including but not limited to all implied warranties and conditions of merchantibility, fitness for a particular purpose, and non-infringement. NatureServe makes no representations about the suitability of the information delivered from this server or any other documents that are referenced to or linked to this server. In no event shall NatureServe be liable for any special, indirect, incidental, consequential damages, or for damages of any kind arising out of or in connection with the use or performance of information contained in any documents provided by this server or in any other documents which are referenced by or linked to this server, under any theory of liability used. NatureServe may update or make changes to the documents provided by this server at any time without notice; however, NatureServe makes no commitment to update the information contained herein. Since the data in the central databases are continually being updated, it is advisable to refresh data retrieved at least once a year after its receipt. The data provided is for planning, assessment, and informational purposes. Site specific projects or activities should be reviewed for potential environmental impacts with appropriate regulatory agencies. If ground-disturbing activities are proposed on a site, the appropriate state natural heritage program(s) or conservation data center can be contacted for a site-specific review of the project area (see Visit Local Programs).

Feedback Request: NatureServe encourages users to let us know of any errors or significant omissions that you find in the data through (see Contact Us). Your comments will be very valuable in improving the overall quality of our databases for the benefit of all users.