[explorer.natureserve.org] Extirpated status: Cryptantha hooveri is only known from three historical occurrences and was last seen in 1939. It occurred in the highly developed low elevation grassland areas in the Central Valley of California. Surveys to relocate this species have been unsuccessful. There are no extant occurrences known to exist, but this is a small, hard-to-identify plant. One occurrence in Contra Costa Co. (the one furthest north) is listed as possibly extirpated; this one was not used in calculating the range extent. The other two historical occurrences in Stanislaus and Madera counties are fairly disjunct. The area of their range is about 400 sq mi. (contributed by Mary Ann Machi)