Penstemon nanus

D. D. Keck

Amer. Midl. Naturalist 23: 607. 1940.

Common names: Low beardtongue
Endemic
Treatment appears in FNA Volume 17. Treatment on page 141. Mentioned on page 126.

Stems ascending, 2–10(–14) cm, densely retrorsely hairy. Leaves basal and cauline, not leathery, densely retrorsely hairy; basal and proximal cauline petiolate, 12–35(–50) × 3–10 mm, blade ovate to lanceolate, base tapered, margins entire, rarely obscurely dentate, apex obtuse to acute; cauline 1–3 pairs, sessile, 13–34 × 2–6 mm, blade oblanceolate to lanceolate or linear, base tapered to slightly clasping, margins entire, apex obtuse to acute. Thyrses continuous, cylindric, axis glandular-pubescent, 2–3(–8) cm, verticillasters 1–5(or 6), cymes 2–4-flowered, 2 per node; proximal bracts lanceolate, 11–20 × 2–6 mm; peduncles and pedicels glandular-pubescent. Flowers: calyx lobes ovate to lanceolate, 4–6 × 1.8–2.2 mm, glandular-pubescent; corolla violet to blue or purple, with reddish violet nectar guides, tubular-funnelform, 12–16 mm, sparsely yellow-lanate internally abaxially, tube 5–6 mm, throat gradually inflated, not constricted at orifice, 4–7 mm diam., rounded abaxially; stamens included, pollen sacs parallel, navicular, 1.7–2 mm, dehiscing completely, sutures papillate; staminode 8–9 mm, included or reaching orifice, 0.8–0.9 mm diam., tip straight, distal 5–6 mm moderately to densely pubescent, hairs orange, to 0.8 mm; style 9–11 mm. Capsules 4–7 × 3–4.5 mm.


Phenology: Flowering May–Jun.
Habitat: Pinyon-juniper woodlands, desert shrublands.
Elevation: 1700–2300 m.

Discussion

Penstemon nanus is known from the ranges and dry valleys of western Beaver and Millard counties. Populations are concentrated in and near the Burbank Hills, Confusion Range, Halfway Hills, Mountain Home Range, and Tunnel Spring and Wah Wah mountains. The parallel pollen sacs and glandular-pubescent thyrse axes of P. nanus distinguish it from P. dolius.

Selected References

None.

Lower Taxa

None.