Penstemon pinifolius
Bot. Gaz. 6: 218. 1881.
Stems erect, (5–) 10–50 cm, glabrous or retrorsely hairy, hairs pointed. Leaves leathery, sparsely retrorsely hairy, hairs pointed, especially along margins, or glabrous; cauline 10–30 pairs, sessile, 4–32 × 0.5–1.2 mm, blade linear, base tapered to clasping, apex acuminate. Thyrses interrupted, secund, (1–) 3–15 cm, axis retrorsely hairy to puberulent, or glabrous, verticillasters 1–7, cymes 1–3-flowered, 1 (or 2) per node; proximal bracts linear, 3–14 × 0.3–1 mm; peduncles and pedicels ascending to erect, glandular-pubescent, sometimes puberulent. Flowers: calyx lobes lanceolate, 5–7 × 1.5–2 mm, scarious-margined, glandular-pubescent, hairs pointed; corolla scarlet, throat sometimes yellow or yellow or orange-spotted, unlined internally, salverform, 25–32 mm, yellow-lanate internally abaxially, tube 4–6 mm, throat slightly inflated, 4–5 mm diam., slightly 2-ridged abaxially; stamens exserted (often hidden by galeate adaxial lobes), filaments glabrous, pollen-sacs opposite, explanate, 0.8–1 mm, sutures smooth; staminode 12–17 mm, included, slightly flattened distally, 0.1–0.2 mm diam., tip straight, distal 9–10 mm densely pilose, hairs yellow, to 1.3 mm; style 21–27 mm. Capsules 5–9 × 3–4 mm. 2n = 16.
Phenology: Flowering Jun–Jul(–Sep).
Habitat: Rocky slopes, cliffs.
Elevation: 1800–3100 m.
Distribution
Ariz., N.Mex., Mexico (Chihuahua), Mexico (Sonora)
Discussion
Penstemon pinifolius has been included as an anomalous member of sect. Leptostemon Trautvetter; R. M. Straw (1962) expressed doubt about that association. It was allied with members of sect. Caespitosi in the molecular study by A. D. Wolfe et al. (2006).
Selected References
None.
Lower Taxa
"/4+timescorollathroat" is not declared as a valid unit of measurement for this property.