Amnicola stygius is a species of very small aquatic snail, an operculate gastropod mollusk in the family Amnicolidae.
Description The length of the shell attains 2.4 mm, its diameter 2.7 mm.
Distribution The holotype was found in a stream in Tom Moore Cave, 3 miles north of Perryville, Perry County, Missouri, USA.
References
External links Field Museum of Natural History: images