Penstemon cyananthus
Bot. Mag. 75: plate 4464. 1849. (as Pentstemon)
Stems decumbent to erect, 5–70(–90) cm, glabrous or sparsely to densely puberulent, not glaucous. Leaves basal and cauline, ± leathery or not, glabrous or basal ones sparsely to densely puberulent, not glaucous; basal and proximal cauline (20–)45–160 × 3–40(–55) mm, blade obovate to oblanceolate, base tapered, margins entire, apex obtuse to acute; cauline 1–6 pairs, sessile or proximals short- to long-petiolate, 16–100 × 5–45(–60) mm, blade ovate or oblanceolate to lanceolate, base cordate-clasping to clasping, apex obtuse to acute. Thyrses continuous or interrupted, cylindric to subsecund, 2–30 cm, axis glabrous, verticillasters 2–12, cymes 3–7-flowered, 2 per node; proximal bracts ovate to lanceolate, 7–80 × (1–)3–35 mm; peduncles and pedicels glabrous, peduncles to 20 mm, pedicels 1–9 mm. Flowers: calyx lobes ovate to lanceolate, 3–6.5 × 1.3–2.6 mm, apex acute to acuminate or cuspidate, glabrous; corolla blue to violet, without nectar guides, ventricose, 12–25(–28) mm, glabrous externally, glabrous internally, tube 6–11 mm, throat gradually inflated, not constricted at orifice, 6–11 mm diam., 2-ridged abaxially; stamens included or longer pair reaching orifice, pollen sacs divergent, navicular, 1.2–2(–2.2) mm, dehiscing incompletely, proximal 1/4–1/3 indehiscent, connective not splitting, sides hispid, hairs white, to 0.5 mm, sutures denticulate, teeth to 0.1 mm; staminode 11–14 mm, included or reaching orifice, 0.3–0.6 mm diam., tip straight to recurved, distal 6–9 mm sparsely to moderately pilose to lanate, hairs orange, yellow, or white, to 1 mm; style 9–16 mm. Capsules 7–15 × 5–10 mm.
Distribution
Idaho, Mont., Utah, Wyo.
Discussion
Varieties 3 (3 in the flora).
Penstemon compactus and P. longiflorus have been treated as elements of the P. cyananthus complex (F. W. Pennell 1920b; D. D. Keck 1940b). All of these taxa occur from the Wasatch Range northward into the Central Rocky Mountains.
Selected References
None.
Lower Taxa
Key
| 1 | Cauline leaf blades lanceolate to oblanceolate; calyx lobes ovate to lanceolate, apices acute to cuspidate, rarely acuminate. | Penstemon cyananthus var. subglaber |
| 1 | Cauline leaf blades ovate to lanceolate; calyx lobes lanceolate, rarely ovate, apices acuminate, rarely acute. | > 2 |
| 2 | Verticillasters 4–12; thyrses 4–30 cm; stems ascending to erect, 20–70(–90) cm; corollas 16–25(–28) mm. | Penstemon cyananthus var. cyananthus |
| 2 | Verticillasters 2 or 3; thyrses 2–6 cm; stems decumbent to ascending, 5–25(–32) cm; corollas 12–16(–20) mm. | Penstemon cyananthus var. judyae |