†Leptoptygma fountainensis Weller 1916
Gastropoda - Murchisoniina - Soleniscidae
Alternative combination: Holopea fountainensis
Full reference: S. Weller. 1916. Description of the Ste. Genevieve limestone fauna from Monroe County, Illinois. Contributions of the Walker Museum, University of Chicago 1:243-265
Belongs to Leptoptygma according to P. J. Wagner 2011
Sister taxa: Leptoptygma golconda, Leptoptygma laetus, Leptoptygma newtonensis, Leptoptygma simplex, Leptoptygma subtilistriatum, Leptoptygma virgatum
Type specimen: Its type locality is Bed No. 8, Fountain Creek, 2 miles southwest of Waterloo, which is in a Chesterian carbonate limestone in the Ste. Genevieve Formation of Illinois.