Physalis ( from φυσαλλίς phusallís "bladder") is a genus of flowering plants in the nightshadefamily (Solanaceae), which grow in warm temperate and subtropical regions of the world. Most of the species, of which 75–90 may exist, are indigenous to the Americas. Cultivated species and weedy annuals have been introduced worldwide. A notable feature is the formation of a large, papery husk derived from the calyx, which partly or fully encloses the fruit. The fruit is small and yellow to orange, similar in size, shape, and structure to a small tomato (hence the name husk tomatoes). At least 46 species are endemic to Mexico. Many Physalis species are called groundcherries.One name for Physalis peruviana is Inca berry; another is Cape gooseberry, not to be confused with gooseberries of the genus Ribes (family Grossulariaceae). Other names used to refer to the fruit are husk cherries, poha berries,and golden berries. A 52 million year old fossil fruit of Physalishas been found in Patagonia.