Oenothera cespitosa var. stellae is a long-lived perennial variety that differs from most other varieties of O. cespitosa in having densely villous gray-green leaves, strongly colonial, forming mounds, and restricted to typically flattened limestone or calcareous substrates. It is most like var. crinita which can also be compact and form mats but which is less villous and is seldom colonial, shorter lived and not limited nor occurring on the same type of habitat. Var. stellae is a Utah endemic, growing at 1700-1950 m in juniper, sagebrush, bitterbrush, and shadscale communities in Emery, Garfield, Kane and Sanpete counties. The type is from the white bar shale knolls of the Winsor member of the Carmel Formation in Kane County, Utah. In the area of the type locality, it grows with other mound-forming taxa including another Utah endemic, Physaria tumulosa.