Penstemon tidestromii
Contr. U.S. Natl. Herb. 20: 379. 1920.
Stems ascending to erect, 25–50 cm, retrorsely hairy, not glaucous. Leaves basal and cauline, ± leathery or not, retrorsely hairy, not glaucous; basal and proximal cauline 40–120 × 4–33 mm, blade obovate to oblanceolate, base tapered, margins entire, apex obtuse to acute; cauline 3–5 pairs, short-petiolate or sessile, 35–70 (–90) × 8–22 mm, blade lanceolate to oblanceolate, base tapered to truncate or clasping, apex obtuse to acute. Thyrses interrupted, secund, 9–22 cm, axis glabrous or sparsely retrorsely hairy, verticillasters 7–15, cymes 5-flowered or 6-flowered, 2 per node; proximal bracts lanceolate, 12–50 × 3–16 mm; peduncles and pedicels glabrous or sparsely retrorsely hairy. Flowers: calyx lobes ovate, 2.5–4 × 1.5–1.7 (–2) mm, margins narrowly scarious, apex obtuse, sometimes acute to cuspidate, glabrous; corolla blue to violet, without nectar guides, ventricose, 13–21 mm, glabrous externally, glabrous internally, tube 5–6 mm, throat gradually inflated, not constricted at orifice, 5–7 mm diam., rounded abaxially; stamens included or longer pair reaching orifice, pollen-sacs divergent, navicular, 1.3–1.7 mm, dehiscing incompletely, proximal 1/3–1/2 sometimes indehiscent, connective not splitting, sides glabrous, sutures denticulate, teeth to 0.1 mm; staminode 8–11 mm, included, 0.6–0.8 mm diam., tip straight, distal 5–8 mm sparsely to moderately pilose, hairs yellow, to 1 mm; style 11–13 mm. Capsules 6–9 × 4.5–6.5 mm.
Phenology: Flowering May–Jul.
Habitat: Sagebrush shrublands, pinyon-juniper woodlands.
Elevation: 1600–2500 m.
Discussion
Penstemon tidestromii is known from Juab and Sanpete counties. Specimens from the San Pitch Mountains with retrorsely hairy stems, corollas obscurely glandular, and pollen sacs 1.5–1.7 mm and sparsely hispid might be hybrids or introgressants between P. subglaber and P. tidestromii. Penstemon leptanthus, known only from the type collection (Ward 280, US), seems to be morphologically confluent with P. tidestromii.
Selected References
None.
Lower Taxa
"/4+timescorollathroat" is not declared as a valid unit of measurement for this property.