Geocarpon minimum

Geocarpon minimum is a species of flowering plant in the carnation family (Caryophyllaceae) which is known by the common names tinytim and earth-fruit. It is a rare plant known from about 34 populations in the US states of Arkansas, Louisiana, Missouri, Texas, and Oklahoma. There are a number of threats to its survival and it was listed as a threatened species of the United States in 1987. Most of the populations are located in Missouri, with a few more in nearby states. It was discovered in Anderson County, Texas, in 2004. The plant was probably widespread on the North American continent long ago, but the climate changed, and it now exists as a relict species in a narrow strip of hospitable habitat. It grows on sandstone glades and outcrops as well as bare, sparsely vegetated areas where the soil contains relatively large amounts of magnesium and sodium salts. It can be found on "slicks" with a coating of lichens and Nostoc cyanobacteria that are very wet after winter rain and then d......read more on Wikipedia.