Paravitrea - Supercoil Snails (Family Zonitidae) 

a Supercoil snail

The Supercoil snails are easily distinguished from other land snails by their many whorls packed in a mid-sized snail with a slightly domed shell.

Three species were found in the databases: the Dimple Supercoil, Paravitrea capsella (Gould 1851), the Dentate Supercoil, Snail, Paravitrea multidentata (A. Binney 1840), and only a single observation of the Domed Supercoil, Paravitrea significans (Bland, 1866).

Characters:  Heliciform, simple lip, subglobose to depressed, umbilicate to perforate, 4-5 mm; unique smooth rounded profile with depressed spire; glossy shell with tight coils.

Comparison: Paravitrea multidentata is the smallest at 2.5-4 mm in diameter or less and not as rounded as the other two. As well, 2-4 transverse rows of small white teeth may be seen through the base of the shell. Paravitrea capsella is the largest in the range of 5-6 mm diameter and Paravitrea significans is ~ 4.5 mm in diameter.

Habitat: wooded areas, among and under leafy and woody debris.

Status: scattered about mostly in southern Indiana.

Key to Paravitrea based on Oesch et al. 2013 and Hotopp et al. 2013:

1a. Periphery located below the midline of the body whorl - Paravitrea significans
1b. Periphery located at or above the midline of the body whorl – 3 

2a. Size smaller, diameter 2.5 to 4 mm; mature shells with one to three rows of teeth or lamellae visible through the base of the shell; and, from Hotopp et al. 2013: tight, regular coils; shell angled; side view is like a pentagon - Paravitrea multidentata
2b. Size larger, diameter about 5-6 mm; mature shells without teeth or internal lamellae, young shells rarely with internal lamellae or teeth - Paravitrea capsella

Dimple Supercoil
Paravitrea  capsella (Gould, 1851)

Dentate Supercoil Snail
Paravitrea multidentata (A. Binney, 1840)

Paravitrea significans (Bland, 1866)

Paravitrea significans (Bland, 1866)

Domed Supercoil
Paravitrea significans (Bland, 1866)