Land Snails

Photo(s): Gastrocopta tappaniana shell © Jeff Nekola.
Illustration © Kathy Schmidt from her series "Land Snails of New York State."

Click photo(s) to enlarge.

Gastrocopta tappaniana (C.B. Adams, 1842)

Family: Vertiginidae
Common name: White Snaggletooth

Identification
Height: ~2.1 mm
Width: ~1.3 mm
Whorls: 4

Gastrocopta tappaniana and its cousin Gastrocopta pentodon differ from all other Virginia pupillid land snails by having a white-clear shell with a simple, peg-shaped angulo-parietal lamella at the top of the aperture. It can be separated from G. pentodon by its fatter shape, with a height/width ratio of more than 1.5. It also consistently occurs in wetter habitats.

Ecology
Gastrocopta tappaniana is found in accumulations of decomposing leaf litter in wooded and open wetland habitats such as riparian, floodplain and swamp woodlands, mesic and wet prairies, open shoreline bedrock outcrops, fens, pocosins, and Sphagnum bogs.

Taxonomy
While some authors have suggested that this taxon is an ecophenotypic variant of G. pentodon (e.g., Bequaert and Miller 1973), statistical analysis of shells in museum collections (Pearce et al., 2007) and of DNA sequences (Nekola et al., 2012) confirms that these two species are highly distinct.

Synonyms for this animal’s name include: Pupa tappaniana, Pupa pentodon form ovata.

Distribution
This animal ranges from central Arizona and southeastern New Mexico, Kansas, and eastern South Dakota, north to central Alberta and Manitoba, northern Ontario, and east to southern Florda and eastern Quebec (Pilsbry, 1948; Nekola & Coles, 2010).

In Virginia this species is currently reported from only scattered locations in central and eastern parts of the state. However, based on its range in surrounding states it is to be expected from across the entire state in its favored wetland habitats.

Conservation
NatureServe Global Rank: G5, Secure.

 

Jeff Nekola 9/2012

Range Map (click to enlarge)