SPECIES STATUS FOR A SONORAN DESERT ANNUAL MEMBER OF OENOTHERA SECT. ANOGRA (ONAGRACEAE)

The taxon most recently known as Oenothera avita W. Klein subsp. arizo nica (Munz) Klein is here elevated to species level. It is easily dist inguished from the perennial taxa of this complex, currently treated a s three subspecies of O. californica, by its annual habit with a tapro ot, stems thickened near the base and tapering toward the apex, buds w ith conspicuous purple spots, each spot at the base of a long hair, lo nger attenuate capsules, and pinnatifid leaves.