Draba abajoensis

Perennials; caudex simple or branched, (sometimes with persistent leaf bases); not scapose. Stems unbranched, (0.6–)1–2.5(–3.5) dm, pubescent proximally, usually glabrous distally, rarely sparsely pubescent, trichomes simple, 0.1–0.5 mm, often with stalked, 2(–4)-rayed ones. Basal leaves rosulate; petiolate; petiole (0.2–1(–2) cm), proximal margin ciliate, (trichomes simple, 0.2–0.7 mm); blade oblanceolate to spatulate, (0.6–)1–3.5(–4.3) cm × (2–)4–10(–14) mm, margins entire or dentate, surfaces pubescent with short-stalked, (2–)4-rayed trichomes, 0.05–0.35 mm, sometimes adaxially with simple ones. Cauline leaves (3–)5–9(–11); sessile; blade broadly ovate to lanceolate or oblong, margins entire or dentate, surfaces pubescent as basal or adaxially also with mostly simple trichomes. Racemes (11–)15–32(–47)-flowered, ebracteate, elongated in fruit; rachis not flexuous, glabrous or pubescent, trichomes simple and short-stalked, 2–4-rayed. Fruiting pedicels horizontal to divaricate-ascending, straight or curved, (5–)7–18(–23) mm, glabrous or sparsely pubescent abaxially, trichomes simple and 2-rayed. Flowers: sepals ovate-oblong, 2.2–3.5 mm, subapically sparsely pubescent, (trichomes simple, short-stalked, and 2-rayed); petals yellow, oblanceolate, 4–6 × 1.5–2 mm; anthers oblong, 0.6–1 mm. Fruits elliptic to elliptic-lanceolate, plane, flattened, 5–9(–12) × 2–3 mm; valves glabrous; ovules 10–18 per ovary; style (0.8–)1.4–2.7(–3.6) mm. Seeds ovoid, 1–1.2 × 0.7–0.8 mm. 2n = 20.

Phenology: Flowering May–Aug.
Habitat: Spruce, fir, or pine forests, subalpine meadows
Elevation: 1900-3800 m

Ariz., N.Mex., Utah.

Discussion

Plants of Draba abajoensis were treated by C. L. Hitchcock (1941), R. C. Rollins (1993), and N. H. Holmgren (2005b) as D. spectabilis. The differences between these taxa in chromosome number and trichome morphology strongly support their recognition as separate species (I. A. Al-Shehbaz and M. D. Windham 2007). Draba abajoensis has been collected from the Chuska and Lukachukai mountains in Apache County, Arizona, Chuska Mountains in San Juan County, New Mexico, and Abajo and La Sal mountains in San Juan and Grand counties, Utah.

Selected References

None.

Lower Taxa