Anogra neomexicana Small, Bull. Torrey Bot. Club 23: 176. 1896 (as neo-mexicana)

Herbs perennial, glabrate prox­imally, strigillose and villous distally; from a taproot, also with lateral roots producing adventitious shoots. Stems erect or ascending, unbranched or branched, 30–60 cm. Leaves in a basal rosette and cauline, rosette weakly developed or absent, at least during flowering, 3–9 × (0.6–)1–2.5 cm; petiole 0–2 cm; blade oblong to lanceolate or narrowly ovate, margins irregularly sinuate-dentate. Flowers 1–several opening per day near sunset; buds nodding, weakly quadrangular, with free tips 0.5–4 mm; floral tube 30–50 mm; sepals 20–30 mm, not spotted; petals white, fading pink, broadly obovate, 20–30 mm; filaments 10–15 mm, anthers 8–15 mm; style 50–70 mm, stigma exserted beyond anthers at anthesis. Capsules erect or strongly ascending, not woody, straight or slightly curved, subcylindrical, obtusely 4-angled, tapering gradually from base to apex, 20–30 × 2–3 mm; sessile. Seeds numerous, in 1 row per locule, dark brown, narrowly obovoid, 1.5 mm. 2n = 14.

Flowering (Mar–)Jun–Jul(–Sep). Uncommon, in rocky or sandy clay or loamy soil in coniferous forest openings, stream valleys, roadsides; 1500–3300 m; Ariz., N.Mex.

Oenothera neomexicana is known from central to western New Mexico west of the Rio Grande Valley, except for the Organ Mountains, and eastern and central Arizona from the White Mountains south to Mount Graham and northwestward across the Mogollon Rim in Coconino and Yavapai counties. Oenothera neomexicana had been assumed to be self-incompatible (W. L. Wagner et al. 2007), but K. E. Theiss et al. (2010) determined one population sampled to be consistently self-compatible.