Penstemon virgatus
in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 113. 1859. (as Pentstemon)
Stems erect, sometimes ascending, (12–)20–65(–90) cm, glabrous or puberulent, not glaucous. Leaves basal and cauline or, often, basal absent, not leathery, glabrous or puberulent, not or slightly glaucous; basal and proximal cauline (20–)60–114 × (3–)12–21 mm, blade oblanceolate or lanceolate, rarely linear, base tapered, margins entire, apex obtuse to acute; cauline 5–11 pairs, sessile, 40–118 × 3–17 mm, blade lanceolate, base tapered to truncate, apex obtuse to acute. Thyrses continuous, sometimes interrupted, secund, (3–)6–40 cm, axis glabrous or retrorsely hairy, verticillasters (3–)6–14, cymes 2–5-flowered, 2 per node; proximal bracts lanceolate to linear, 19–74(–98) × 2–10 mm; peduncles and pedicels glabrous or retrorsely hairy. Flowers: calyx lobes ovate to elliptic, 2.2–5 × 1.3–2.2 mm, glabrous or puberulent; corolla violet to lavender, pink-lavender, or purple, with reddish purple nectar guides, ventricose, 17–27 mm, glabrous externally, sparsely white-villous, rarely glabrous, internally abaxially, tube 5–8 mm, throat gradually to abruptly inflated, slightly constricted at orifice, 6–8 mm diam., rounded abaxially; stamens: longer pair slightly exserted, pollen sacs divergent to opposite, navicular, 1.5–1.8 mm, dehiscing completely or incompletely, connective splitting or not, sides glabrous, sutures smooth or papillate; staminode 12–14 mm, reaching orifice or exserted, 0.7–1.2 mm diam., tip straight, glabrous; style 13–15 mm. Capsules 9–14 × 4–8 mm.
Distribution
Ariz., Colo., N.Mex., Wyo.
Discussion
Varieties 2 (2 in the flora).
Penstemon virgatus is treated here to include two essentially allopatric varieties. F. S. Crosswhite (1967c) circumscribed the species more broadly, including as subspecies two additional taxa treated here as species: P. pseudoputus and P. putus.
Whole plants or roots of Penstemon virgatus are used by the Ramah Navajo of western New Mexico as a medicine (D. E. Moerman 1998).
Selected References
None.
Key
| 1 | Stems puberulent; leaves ± puberulent. | Penstemon virgatus var. virgatus |
| 1 | Stems glabrous; leaves glabrous. | Penstemon virgatus var. asa-grayi |