Pentachaeta aurea

Pentachaeta aurea is known from southwestern California and northwestern Baja California, where it occurs from the coast to lower elevations of the Transverse and Peninsular Ranges. Occurrences of this species have not been mapped; approximately 225 distinct herbarium specimens are known to have been collected in California to date (about 53 of these collected after 1989) and at least 8, and probably more, specimens have been collected in Baja California. This species has likely been reduced somewhat from its historical abundance, particularly along the southern California coast. Non-native plants are the most frequent rangewide threat; other threats include development, habitat alteration, and vehicles.

Southwestern California and northwestern Baja California; occurs from the coast to lower elevations of the Transverse and Peninsular Ranges, including the San Gabriel, San Bernardino, and San Jacinto Mountains (Hickman 1993, Keil 2007). In California, occurs from southeastern Los Angeles County and southwestern San Bernardino County south through Orange, western Riverside, and San Diego Counties (Keil 2007). In Baja California, it occurs on the northwest peninsula (Wiggins 1980).

Occurrences of this species have not been mapped. Approximately 225 distinct herbarium specimens are present in the Consortium of California Herbaria database (2009), about 53 of which were collected after 1989. Number of collections from Baja California unknown; 8 specimens retrieved through GBIF database (2009), but more may exist.

On the whole, this species is considered "fairly endangered" in California, with non-native plants being the most prominent rangewide threat (CNPS 2009). P. aurea ssp. allenii (restricted to southwestern Orange County) (Keil 2007) is considered "seriously threatened", with threats including development, habitat alteration, and vehicles (CNPS 2009).