Amblema plicata

Analysis of genetic structure (Elderkin et al., 2007) showed low structure among rivers and rainages separated by very large geographical distances, indicating high effedtive population size and/or highly vagile fish hosts. Northern populations were likely founded from at least two glacial refugia following the Pleistocene.

This species is considered common and widespread throughout much of the U.S. and Canada and is considered stable, or in some cases expanding, throughout its range.

This species ranges from the coastal plain portion of Gulf drainages from the Escambia River in Florida west to Texas and northward into the Mississippi River drainage (Mulvey et al,. 1997). Butler (1989) lists the distribution as throughout the Interior Basin and from the San Antonio River, Texas, east to the Choctawhatchee River, but not from the Yellow River. In Canada, it is restricted to southern Ontario, southern Manitoba, and southeastern Saskatchewan, but is widely distributed and often abundant In Canada, this species is restricted to the Lake Erie drainage in Ontario (Metcalfe-Smith and Cadmore-Vokey, 2004). It extends into the Niagara River drainage in western New York (Strayer and Jirka, 1997).

It is in the Cache and White (Christian, 1995; Christian et al., 2005; Gordon, 1982; Gordon et al., 1994), lower Arkansas (Gordon, 1985), St. Francis (Ahlstedt and Jenkinson, 1991), Ouachita (Posey, 1997; Posey et al., 1996), and Poteau (Vaughn and Spooner, 2004) drainages, Arkansas. In South Dakota, it is in the upper and middle Big Sioux and tributaries (Skadsen and Perkins, 2000), James and Vermillion Rivers (Backlund, 2000; Perkins and Backlund, 2003). It is throughout E and SE Texas and San Antonio and Guadalupe systems N and E; Nueces River (Howells et al., 1996); Village Creek (Hardin/Tyler/Polk Cos.) (Bordelon and Harrel, 2004). In Kansas, it is widespread in the E third and relictual N and W (Couch, 1997); also Wakarusa (Tiemann, 2006). It is in the Spring River drainage, Kansas and Oklahoma (Branson, 1966). Oklahoma: Verdigris (Boeckman and Bidwell, 2008), Neosho, Boggy, Clear Boggy, Blue, Kiamichi, Little (Vaughn and Taylor, 1999), Chikaskia, Canadian, Poteau, and Mountain Fork (Spooner and Vaughn, 2007) systems (Branson, 1982; Vaughn, 2000). It is widespread and common in Illinois and most of Wisconsin (Cummings and Mayer, 1992; 1997; Mathiak, 1979; Schanzle et al., 2004; Tiemann et al., 2005). In Indiana: Blue (Sietman et al., 1995), Tippecanoe (Cummings and Berlocher, 1990), E Fork White (Harmon, 1992), Muscatatuck (Harmon, 1989), St. Joseph (Pryor, 2005). In Minnesota, it is in the W and S but absent from Lake Superior, Rainy River, and most of Mississippi drainage above St. Anthony Falls (Sietman, 2003); including Red River (Cvancara, 1970). It was widespread and common in Ohio (Watters, 1992; 1995; Lyons et al., 2007; Grabarkiewicz, 2008; Hoggarth et al., 2007); but range has decreased in the past decade (Watters et al., 2009). In Tennessee, it is in most drainages (Parmalee and Bogan, 1998). It is statewide in Kentucky (Cicerello and Schuster, 2003; Evans, 2008); Red (Clark, 1988), Middle Green (Gordon, 1991) and Barren Rivers (Cochran and Layzer, 1993). In West Virginia, it is in the Middle and lower Ohio (Zeto et al., 1987), Mud Rivers (Guyandotte drainage) (Schmidt and Zeto, 1986), Kanawha (Morris and Taylor, 1992); and Copper Creek in Virginia (relict) (Fraley and Ahlstedt, 2000). It is common and widespread throughout Louisiana (Vidrine, 1993). In Mississippi, it is in the Mississippi River N and S, Big Black, Yazoo, Tennessee, Pearl, Pascagoula, and Tombigbee drainages (Jones et al., 2005). It is reported from the Escambia and Yellow (Picket Wretch Lake) drainages in Florida and Alabama (also Choctawhatchee River, Walton Co.) (Butler, 1989) but now extirpated (Blalock-Herod et al., 2005). In the Alabama and Mobile basin, it is in the Tennessee and Mobile basins except upper Tallapoosa and possibly Coosa drainage (Williams et al., 2008). It is historic from the Black Warrior River, but was in the upper Tombigbee in Sumter and Greene Cos., Alabama (Williams et al., 1992; McGregor et al., 1999); also Bear Creek drainage, AL/MS (McGregor and Garner, 2004). In the Big Blue system (NE Nebraska and Kansas) it was only in the Kansas portion (6 sites), and 1 subfossil N of the border (Hoke, 2005). In the Little Blue basin weathered shells are in the Kansas portion (Hoke, 2004). I is in Tonawanda Creek (Niagara drainage), western New York (Marangelo and Strayer, 2000) and in Muddy Creek (French Creek drainage), Crawford Co., Pennsylvania (Mohler et al., 2006). It occurs in the St. Clair/Detroit drainage in Michigan (Strayer, 1980; Trdan and Hoeh, 1993) and S upper peninsula (Goodrich and Van der Schalie, 1939; Badra and Goforth, 2003). In Canada, it is widespread from southern Manitoba (incl. Assiniboine- Watson, 2000), northern (Churchill River, Stony Rapids east of Lake Athabasca) and southeastern Saskatchewan (Frenchman, Assiniboine, Qu'Appelle, North and South Saskatchewan, Carrot Rivers; Moose Jaw, Swift Current Creeks); and the Lake Erie drainage in Ontario (Metcalfe-Smith and Cadmore-Vokey, 2004).