Width 6.7 mm, 5 1/2 whorls, increasing slowly; surface with fine granular finish, giving a matte appearance, with numerous sharply defined striae; apical whorl glossy; color orange-brown (variable - dark orange-brown to light yellow), aperture with white border.
Shell imperforate; aperture sub-triangular; peristome thickened outwardly, with raized keel behind lip, giving lip double edged appearance; lip constricted near columella, though variably so and not clearly evident in this specimen.
Spire conic, sides shallowly convex in profile; whorls flattened above, with sutures not impressed; peripheral keel obsolete.
Aperture oblique; suture slightly descending to aperture.
Operculum thin, transparent, teardrop shaped, broadly rounded at base, narrowly rounded at apex, slightly thickened along parietal wall, with spiral or 'S' shaped growth line at base, surface finely wrinkled.
Color variation - dark orange-brown to light yellow, lip white to yellow.
Notes:
Locality: Missouri, Boone Co., 3 mi. SE of Rockbridge State Park, Three Creeks Conservation Area, under rocks and leaves at base of bluffs along Turkey creek, above flood zone.
This locality may be the southern limit for recent populations of this species. In Pleistocene times it was abundant along the Missouri River and ranged along the Mississippi River as far south as southern Mississippi.
[Pilsbry, 1948, LMNA, II(2):1086-1090]
[Hubricht, 1985, Fieldiana, 1359:3-4, map 1]