''Physalis infinemundi'' is an extinct species of the genus ''

Physalis ''Physalis'' (, , , , from φυσαλλίς ''phusallís'' "bladder") is a genus of approximately 75 to 90 flowering plants in the Solanum, nightshade family (biology), family (Solanaceae), which are native to the Americas and Australasia. At l ...

'' (which includes

Cape gooseberry ''Physalis peruviana'' is a species of plant in the nightshade family ( Solanaceae) native to Colombia, Ecuador and Peru. It is commonly known as Cape gooseberry, goldenberry or ground cherry, as poha in Hawaii, and as Harankash in Egypt, whil ...

tomatillo The tomatillo (''Physalis philadelphica'' and ''Physalis ixocarpa''), also known as the Mexican husk tomato, is a plant of the nightshade family bearing small, spherical, and green or green-purple fruit of the same name. Tomatillos originated ...

, and ground cherries) known from two fossilised fruit found in the Laguna del Hunco Formation of

Chubut Province Chubut ( es, Provincia del Chubut, ; cy, Talaith Chubut) is a province in southern Argentina, situated between the 42nd parallel south (the border with Río Negro Province), the 46th parallel south (bordering Santa Cruz Province), the Andes ra ...

, Argentina dating to the

Eocene The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...

, around 52 million years old. The species name derives from "in fine mundi" means "at the end of the earth" referring to the fact that it grew in the far south. The fossil was considerably older than the diversification ages predicted by previous

molecular clock The molecular clock is a figurative term for a technique that uses the mutation rate of biomolecules to deduce the time in prehistory when two or more life forms diverged. The biomolecular data used for such calculations are usually nucleoti ...

studies of

Solanaceae The Solanaceae , or nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of agricultural crops, medicinal plants, spices, weeds, and orn ...

, which estimated that the family as a whole originated 30 million years ago. The fossils are very similar to modern ''Physalis'' species, with 5 distinct lobes. The environment at the time of deposition is thought to have been a rainforest.

References

infinemundi Eocene plants {{paleobotany-stub