Lampsilis siliquoidea shell description:

“Shell oblong, elongate, ovate; dorsal and ventral margins nearly parallel; dorsal margin straight, ventral margin straight, sometimes gently rounded; anterior end uniformly rounded, posterior end straight dorsally, angled where it meets the dorsal margin, rounded below.  Shell thickness is uniform; size to 13.2cm; shell moderately compressed to moderately inflated, the later seen in females who become noticeably swollen in the postero-ventral region; Posterior ridge not prominent, gently rounded dorsally.  Beaks broad, slightly raised above the hinge line; inequipartite; beak sculpture has several fine lines sharply drawn up in the middle.  Growth-rest lines noticeable but not prominent features on the shell.  Epidermis shiny, light yellow in young shells, becoming dark chestnut in some old specimens; bright green rays that uniformly cover the shell may be broad to fine capillary type rays; some are rayless. Left valve has two erect, compressed, emarginated pseudocardinal teeth; lateral teeth short slightly curved and relatively low.  Right valve has a large erect, emarginated pseudocardinal tooth; there is a small lamellar tooth anteriorly; lateral tooth thin and straight.  Interdentum absent; beak cavity shallow; nacre white, iridescent posteriorly” (Mather 2007).