Depressed Slipper Snail

Shell to 43 mm; shell flat or taking shape of substrate. Septum relatively small, less than half length of shell. Color pure white inside and out; outside surface sometimes with thin, tan periostracum. Although having a shell virtually indistinguishable from that of Crepidula atrasolea Collin, 2000, C. depressa has white foot and planktotrophic development, whereas C. atrasolea has a blackish foot and is a direct developer. (The illustrated specimens, lot BMSM 15001, were examined and cited in Collin, 2000.)