Bot. Gaz. 52: 273. 1911.
Stems ascending to erect, (14–) 30–60 (–90) cm, glabrous or retrorsely hairy, not glaucous. Leaves basal and cauline, not leathery, glabrous or retrorsely hairy, not glaucous; basal and proximal cauline 50–130 (–150) × 5–15 (–25) mm, blade oblanceolate to elliptic, base tapered, margins entire, usually undulate, apex obtuse to acute; cauline (2 or) 3–5 (–8) pairs, petiolate or sessile, 49–90 × 5–15 mm, blade lanceolate, base tapered, truncate, or clasping, margins undulate, apex acute to acuminate. Thyrses interrupted or continuous, cylindric to ± secund, (2–) 9–20 (–40) cm, axis glabrous, verticillasters (3–) 5–9 (–25), cymes 2–8 (–10) -flowered, 2 per node; proximal bracts lanceolate, 18–50 (–80) × 2–20 mm; peduncles and pedicels glabrous. Flowers: calyx lobes ovate, 3–5 × 1.6–2.8 mm, margins broadly scarious, apex rounded to acute or mucronate, glabrous; corolla violet to blue or purple, without nectar guides, funnelform to weakly ventricose, 18–22 mm, glabrous externally, glabrous internally, tube 6–8 mm, throat gradually inflated, not constricted at orifice, 5–8 mm diam., slightly 2-ridged abaxially; stamens included or longer pair reaching orifice, pollen-sacs divergent to nearly opposite, navicular-sigmoid, 1.4–1.7 mm, dehiscing incompletely, proximal 1/5 indehiscent, connective not splitting, sides glabrous, sutures denticulate, teeth to 0.1 mm; staminode 9–12 mm, included, 0.6–1 mm diam., tip straight to recurved, distal 4–8 mm sparsely to moderately pilose, hairs yellow, to 1 mm; style 13–16 mm. Capsules 9–14 × 6–8 mm.
Phenology: Flowering May–Jul.
Habitat: Sagebrush shrublands.
Elevation: 600–2000 m.
Penstemon perpulcher is common in the Snake River Plains of southern Idaho (Ada, Bannock, Boise, Canyon, Cassia, Custer, Elmore, Gooding, Minidoka, Oneida, Owyhee, Payette, and Twin Falls counties) and western Oregon (Malheur and Wallowa counties).
"/4+timescorollathroat" is not declared as a valid unit of measurement for this property.