Penstemon ammophilus
Brittonia 34: 381, fig. 1. 1982.
Stems decumbent to ascending, 5–26 cm, usually ± fistulose, glutinous and covered with sand, not glaucous. Leaves basal and cauline, not leathery, glutinous and covered with sand, not glaucous; basal and proximal cauline 18–80 × 4–15 mm, blade oblanceolate, base tapered, margins entire, crisped, apex obtuse to acute; cauline 2–5 pairs, sessile, 15–75 × 2–8 mm, blade oblanceolate to lanceolate, base tapered to truncate, margins crisped, apex rounded or obtuse to acute. Thyrses continuous, cylindric, 4–15 cm, axis glutinous and covered with sand, verticillasters 4–10, cymes 1–6-flowered, 2 per node; proximal bracts lanceolate, 14–45 × 2–5(–8) mm; peduncles and pedicels glutinous and covered with sand. Flowers: calyx lobes lanceolate, 5–6.5 × 1–2 mm, glutinous and covered with sand; corolla lavender to blue-lavender, with violet nectar guides, weakly ventricose, 14–17 mm, glabrous externally, usually glutinous and covered with sand distally, especially on lobes, glabrous internally, tube 5–6 mm, throat gradually inflated, not constricted at orifice, 5–6 mm diam., slightly 2-ridged abaxially; stamens: longer pair reaching orifice, pollen sacs opposite, navicular, 0.9–1.4 mm, dehiscing completely or incompletely, connective splitting or not, sides glabrous, sutures papillate; staminode: 8–9 mm, included, 0.3–0.5 mm diam., tip straight, distal 4–5 mm sparsely papillate, papillae violet, to 0.2 mm; style 10–12 mm. Capsules 3.5–6.5 mm.
Phenology: Flowering May–Jun.
Habitat: Sand dunes, ponderosa pine forests, mixed shrublands.
Elevation: 1800–2200 m.
Discussion
Penstemon ammophilus is known from Garfield, Kane, and Washington counties. Populations occur on aeolian sand, derived from the Navajo Sandstone. The fistulose stems of P. ammophilus are unique in Penstemon.
Selected References
None.