Cryptantha crinita Greene (silky cryptantha) is a rare native annual plant previously known solely from alluvial soils of the northern Sacramento Valley in California. It has been considered a lowland species (85–300 m) associated with creekbeds. Several recent collections (1990–2004) made in upland habitats at 850–1200 m show that the species is more common and has a wider ecological amplitude than previously thought. Although the habitats of the upland and valley sites differ, they are both characterized by a sparse vegetative cover which appears to be a key factor for establishment and growth of C. crinita.