Vallonia - Vallonia Snails (Family Valloniidae)

a Vallonia snail

The Trumpet or Vallonia snails are very beautiful small (1.5-3 mm) trumpet-like species, some with notable shell architecture of raised “ribs” and a reflected apertural lip. Those characters are much different than those of Triodopsis and Daedalochia, with whom they share Group E3 and the major characters of being wider than tall but depressed to discoidal, umbilicate, and with a reflected lip.


The databases give 6 species of Vallonia for Indiana but Nature Serve only lists 4. The commonest species are these three: Vallonia costata, the Costate Vallonia Snail, Vallonia excentrica, the Iroquois Vallonia Snail, and Vallonia pulchella, the Lovely Vallonia Snail. The fourth species listed in Nature Serve is Vallonia gracilicosta, the Multirib Vallonia Snail. The other two species are Vallonia parvula, the Trumpet Vallonia Snail, and Vallonia perspectiva, the Thin-lip Vallonia Snail. These last three species, though rare (if really present) in Indiana are found in Illinois. 

Among the tiny heliciform depressed-to-discoidal snails they are unique for their trumpet-like reflected lip. Their small size of course, means collecting is a bit of work, carefully examining organic debris in the forest floor.

Characteristics: depressed to discoidal; aperture rounded and lip reflected; umbilicate; whorls with irregularly spaced high ribs or ridges; ~1.5-3 mm in diameter.

Habitat: Can be found in both upland and floodplain woodlands, in and around woody debris or rocks, or in soil; may be found in glades and prairies.

Status: Three main species are potentially widely scattered, three others less common.

Key to Vallonia based on Oesch et al. 2013, Dourson 2015, and Hotopp et al. 2013.

1a. Shell with faint growth lines, but not clearly ribbed - 2
1b. Shell ribbed – 3

2a. Outer lip reflected - Vallonia pulchella
2b. Outer lip not reflected - Vallonia excentrica

3a. Aperture lip thickened within - 4
3b. Aperture lip thin - Vallonia perspectiva

4a. Shell diameter about 1.6-2.0 mm; major ridges 30-38 on the last whorl - Vallonia parvula
4b. Shell diameter about greater than 2 mm – go to 5

5a. With 45-55 ribs or ridges on the last whorl - Vallonia gracilicosta
5a. With 20-35 paper-thin ribs or ridges in last whorl - Vallonia costata

For images of all except Vallonia gracilicosta, go to Hotopp et al. 2013 and find the species. Vallonia parvula is imaged here. For images of Vallonia gracilicosta, go here.

Vallonia parvula Sterki, 1893

Costate Vallonia Snail
Vallonia costata (Muller, 1774)

Iroquois Vallonia Snail
Vallonia excentrica Sterki, 1893

Lovely Vallonia Snail
Vallonia pulchella (Muller, 1774)

Multirib Vallonia Snail
Vallonia gracilicosta Reinhardt, 1883

Trumpet Vallonia Snail
Vallonia parvula Sterki, 1893

Thin-lip Vallonia Snail
Vallonia perspectiva Sterki, 1893