Thompson’s Sandwort (Eremogone franklinii var. thompsonii)
Franklin’s Sandwort (Eremogone franklinii (Douglas ex Hooker) R. L. Hartman & Rabeler) (see photo) is a quite widespread cushion-forming plant species that occurs in the western USA.
The variety discussed here, however, is known only from the type that was collected in the 1930s somewhere in Gilliam County in Oregon, USA. It may be extinct, however, it was found once in the 1980s in Benson County, Washington so may in fact be still existing.
The Rusty Sandwort (originally described as Arenaria ferruginea Duthie ex F. N. Williams ) was restricted to the valleys of the rivers Dhauli and Kali in the Kumaon Division of Uttarakhand, India, it is known exclusively from material that had been collected in 1886 and is most likely extinct.
The species probably disappeared due to heavy grazing by feral ungulates.
 Richard K. Rabeler; Warren L. Wagner: Eremogone (Caryophyllaceae): new combinations for Old World species. PhytoKeys 50: 35-42. 2015