Members of the genus Physalis are known as groundcherries. They aren’t true cherries (family Rosaceae), they’re members of the family Solanaceae. This family includes nightshade, tomatoes, eggplants, peppers, potatoes, petunias, and tobacco.
This longleaf groundcherry (Physalis longifolia, Solanaceae) is unique among its genus for its long (lanceolate), coarsely-serrated leaves. Although it can be considered a weed, the tomato-like fruit are edible. The fruit grow inside a papery shell (shown above) that is derived from the sepals.
Perhaps the best-known groundcherry is the tomatillo (Physalis philadelphica, Solanaceae). Tomatillos are popular in Latin American cuisine as the basis for green sauces.