Penstemon rupicola

(Piper) Howell

Fl. N.W. Amer., 510. 1901. (as Pentstemon)

Common names: Cliff beardtongue
Endemic
Basionym: Penstemon newberryi var. rupicola Piper Bull. Torrey Bot. Club 27: 397. 1900
Treatment appears in FNA Volume 17. Treatment on page 92. Mentioned on page 86, 87.

Subshrubs, cespitose. Stems ascending to erect, 3–16 cm, puberulent to pubescent, not glaucous. Leaves persistent, 3–8 pairs, distals usually distinctly smaller than proximals, short-petiolate or sessile, 4–22 × 3–14 mm, blade round to elliptic or spatulate, base tapered to cuneate, margins ± serrate, apex rounded to obtuse, rarely acute, glabrous or hairy, usually glaucous. Thyrses continuous, ± secund, 1–3 cm, axis hairy proximally, pubescent or glandular-pubescent distally, verticillasters 1–3, cymes 1-flowered; proximal bracts elliptic to ovate, 3–9 × 2–6 mm; peduncles and pedicels ascending to erect, glandular-pubescent. Flowers: calyx lobes lanceolate-elliptic to oblong, 6–11 × 2–2.8 mm, glandular-pubescent; corolla pink to red, pinkish lavender, or rose red, essentially unlined internally but abaxial ridges usually white, not personate, funnelform, 25–36 mm, glabrous externally, glabrous internally or sparsely white-lanate abaxially, tube 8–12 mm, throat 6–8 mm diam.; stamens: longer pair exserted, pollen sacs 1–1.5 mm; staminode 13–15 mm, slightly flattened distally, 0.1 mm diam., tip straight, glabrous or distal 1–2 mm sparsely villous, hairs yellow, to 0.8 mm; style 26–30 mm. Capsules 7–9 × 5–7 mm. 2n = 16.


Phenology: Flowering Jun–Jul.
Habitat: Cliffs, rock outcrops.
Elevation: 60–2400 m.

Discussion

Penstemon rupicola occurs largely in the Siskiyou Mountains and Cascade Range from northern California to northern Washington. It is partly sympatric with and forms hybrids with P. cardwellii, P. davidsonii var. davidsonii, and P. fruticosus var. fruticosus (A. D. Every 1977). Hybrids between P. rupicola and P. davidsonii var. davidsonii are encountered frequently in the vicinity of Crater Lake National Park and Mt. Hood (Every).

Selected References

None.

Lower Taxa

None.