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The usually straight ventral margin is mostly parallel with the dorsal margin and the posterior margin is broadly rounded. Shell thickness varies from thin to solid. Johnson. (1970) synonomized sixteen described species from the greater CSB with E. complanata: This species is widely distributed along the Atlantic Slope from Altamaha River Basin. in Georgia north to the St. Lawrence River Basin, and west to Lake Superior and parts of the Hudson Bay Basin. It can be found in a variety of habitats from large rivers and, lakes to small headwater, streams. The species is widespread and common throughout its range and considered "Stable' (Williams et al. 1993). It was found in relatively high numbers, throughout the channel of Collins Creek with multiple size, or age classes present. Elliptio iderxna (variable spike) - Described from the Savannah River near Augusta Georgia (Conrad 1834), this highly variable species represents a complex of nearly 50 species (Johnson 1970). The shell shape is oblong, subelliptical, or subrhomboid, with a prominent posterior ridge, and moderately elevated beaks. The periostracum is usually smooth and greenish yellow to tawny- brown. This species is considered common and currently stable throughout its range (Williams et al. 1993). It was found in relatively low numbers, primarily in rocky riffles, and was represented by mostly large, older individuals. Pyganadon cataracts (eastern floater) - Described by Say (1817) in the deep part of a milldam presumably near Philadelphia, this species is wide ranging in the Atlantic drainages from the lower St. Lawrence River Basin south to the Altamaha River Basin, Georgia, and in the Alabama-Coosa River drainage, and the Apalachicola and Coctawhatchee River Basins, Florida.. 'the shells of this species are uniformly thin, and lack hinge teeth. The shell shape is ovate, subelliptical and elongate, with an evenly rounded anterior margin and a broadly rounded ventral margin. The periostracurn is light to dark green with broad green rays on the posterior slope. Grtm.ann (1919) recognized three generalized shell forms, the pond form, the creek/small river form, and the big river form, that were related to environmental conditions. The pond .form occurs in small ponds with muddy substrates, and is characterized by very thin elongate inflate. shells. The creek form occurs in riffle -pool habitats in gravel substrates, and is much thicker and more compressed. The big river farm is generally short and inflated and occurs in soft substrates. This species is considered common and currently stable throughout its range (Williams et al. 1993). Only one shell valve of this species. was found in the surveyed section of Collins Creek. Uniomerus carolinianus (Florida pondhorn) - Described by (Bose 1801 -1804) from "the Carolinas," this species ranges from Ocrnulgee River in Georgia north to the Chowan River in Virginia. Johnson (:1970) synonorl zed the U.. ineptus Lea (1852) described from the Savannah River Basin with U. carolinianus. Shells are usually inflated rhomboid, to long rhomboid and reach lengths to 114 mm. The species generally exhibits a dark brown to black periostracum with a slightly roughened, satiny sheen. Teeth of the left valve contain two subequal pseudocardinals, often with a vestigal tooth above them., and one lateral tooth. This species is considered common. and currently, stable throughout its range (Williams et al. 1.993). It was found in relatively low. numbers Freshwater Mussel Survey 4 Orange County Transfer Station May 2009 TCG Job # 3250