A rare and endangered mollusk, Guppya sterkii (also known as Brilliant Granule, Sterki's Granule, and Northern Granule) is an extremely small terrestrial snail found within Wisconsin. Eating mostly plant material, the Brilliant Granule lives among the leaves in the Door and Garden Peninsulas ("What do snails eat?", 2011, "Brilliant Granule (Guppya sterkii)", 2009).


Being a member of the snail and slug family, this unique snail has a shell diameter of no more than 1.3 mm and has the ability to traverse land while utilizing a modified lung ("Guppya sterkii", 2007).