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)

revised: 1/23