Guppya - Granule Snails (Family Helicarionidae) 

Sterki’s Granule
Guppya sterkii (Dall, 1888)

Characteristics: 1.2-1.3 mm in diameter; 3.5-4 whorls; shape like depressed beehive, with very rounded whorls and well-to moderately-impressed sutures; shell minutely perforate to imperforate; minute spiral striae may be hard to see and radial striae weak.

Comparisons: Hottop et al. (2020) note (see link above) that “Because G. sterkii is so small, it can be confused with immature shells of other species, but can be separated by its closed umbilicus and tighter whorl pattern.” Oesch et al. (2015) notes that Punctum minutissimum is similar in size but is easily separated by its closed umbilicus and by its smooth surface sculpture compared to the ribs (riblets) of Punctum.

Habitat: this is a species of leaf litter including moist leaf litter in woodlands, hillsides and ravines, and along bluffs and rock outcrops.

Status: An uncommon snail, collected in five counties in south-central and south-east Indiana.