Brittonia 50: 159, fig. 1F–J. 1998.
Herbs. Stems ascending to erect, 6–20 cm, retrorsely hairy, hairs appressed, white, ± scalelike, not glaucous. Leaves cauline, opposite, retrorsely hairy, hairs white, scalelike, not glaucous; cauline 1–4 pairs, petiolate, 15–45 × 7–24 mm, blade ovate to spatulate or lanceolate, base tapered, margins entire, apex rounded to acute. Thyrses interrupted, cylindric, 2–7 cm, axis glandular-pubescent, sometimes also retrorsely hairy or appressed-hairy proximally, hairs white, scalelike, verticillasters 3 or 4(–7), cymes (1 or)2–5-flowered, 1 or 2 per node; proximal bracts lanceolate, 9–25 × 1–5 mm; peduncles and pedicels ascending, glandular-pubescent. Flowers: calyx lobes lanceolate, 4–4.8 × 1.4–2 mm, glandular-pubescent; corolla violet to lavender, without nectar guides, abaxial ridges usually white, weakly ventricose, 15–20 mm, glandular-pubescent externally, glabrous internally, tube 4–6 mm, throat gradually inflated, 4–5 mm diam., 2-ridged abaxially; stamens included or longer pair reaching orifice, filaments glabrous, pollen sacs nearly parallel to divergent, 1.1–1.6 mm, distal 2/3 indehiscent, sides glabrous, sutures denticulate, teeth to 0.1 mm; staminode 8–10 mm, exserted, 0.3–0.6 mm diam., glabrous or sparsely pilose, hairs yellow, to 0.2 mm; style 10–13 mm. Capsules 6–8 × 4–5 mm. 2n = 16.
Phenology: Flowering Jun–Aug.
Habitat: Sandy-loam soils, steep volcanic talus slopes.
Elevation: 2300–2900 m.
Penstemon tiehmii is known only from Mount Lewis in the Shoshone Range in Lander County.