Jussiaea subacaulis Pursh, Fl. Amer. Sept. 1: 304. 1813 (as Jussieua); Camissonia subacaulis (Pursh) P. H. Raven; Oenothera heterantha Nuttall; O. heterantha var. taraxacifolia S. Watson;O. subacaulis (Pursh) Garrett; O. subacaulis var. taraxacifolia (S. Watson) Jepson; Taraxia heterantha (Nuttall) Small; T. taraxacifolia (S. Watson) A. Heller

Herbs usually glabrate, rarely sparsely strigillose, especially on leaf blade veins and margins; taproot thick, deep, sometimes branched in age, producing new rosettes. Leaves 2–22 × 0.7–4.2 cm; petiole narrowly winged, 1–12 cm; blade lanceolate to narrowly elliptic, base attenuate, margins usually subentire to sinuate, sometimes deeply and irregularly pinnatifid, apex acuminate. Flowers opening near sunrise; floral tube 1.5–3 mm, with short, matted hairs inside near base; sepals 4–15 mm, mostly glabrous, sometimes very minutely strigillose; petals yellow, 5–16 mm, often apiculate; episepalous staminal filaments 1.8–6.5 mm, epipetalous ones 0.5–2.5 mm, anthers 0.9–2 mm; sterile prolongation of ovary 15–80 mm, style 4–8.5(–11) mm, glabrous or sparsely pubescent near base, stigma usually surrounded by longer anthers at anthesis, rarely exserted beyond anthers. Capsules 4-angled, oblong-ellipsoid, 11–28 × 5–8 mm, walls thick, scarcely distended by seeds, becoming blackened and persistent on plants for 1+ years after shedding seeds; rarely with pedicel to 10 mm. Seeds uniformly tan to light brown, ellipsoid-oblanceoloid, 1.3–1.9 × 0.6–1 mm, coarsely pitted. 2n = 14.

Flowering late Mar–Jul. Meadows, seasonally moist open places, from foothills to mountains; 400–2900 m; Calif., Colo., Idaho, Mont., Nev., Oreg., Utah, Wash., Wyo.

Taraxia subacaulis occurs well inland from Pacific coastal areas. Its only occurrence in Colorado is in Moffat and Routt counties. P. H. Raven (1969) determined Taraxia subacaulis to be self-compatible and, usually, facultatively autogamous. The species is distinctive, but is sister to T. tanacetifolia in molecular analyses (R. A. Levin et al. 2004; W. L. Wagner et al. 2007).