Pupilla bigranata

Pupilla bigranata is a nomen dubium that was used for some forms of the land snails Pupilla triplicata and Pupilla muscorum, but none of these forms represent a separate species, therefore such species as Pupilla bigranata does not exist.
Considering that in the original Emil [Adolf Rossmässler|Rossmässler]'s description the type [locality (biology)|type locality] was not indicated and that type specimens are not preserved, it is not possible to determine whether Pupa bigranata Rossmässler, 1839 is synonym of Pupilla triplicata or Pupilla muscorum.