Penstemon glaber
Penstemon glaber var. alpinus
sawsepal penstemon, southern smooth beardtongue, western smooth beardtongue
alpine sawsepal penstemon
ascending, (10–)50–65(–80) cm, glabrous or puberulent to pubescent, not glaucous.
glabrous or puberulent proximally.
basal and cauline, or basal absent or reduced, not leathery, glabrous or puberulent to pubescent, not glaucous;
basal and proximal cauline 20–80(–155) × 5–20(–45) mm, blade obovate to oblanceolate or lanceolate, base tapered, margins entire, usually undulate, apex obtuse to acute, sometimes mucronate;
cauline (2 or)3–6(–8) pairs, sessile, 27–120(–150) × (6–)22–35(–43) mm, blade lanceolate, base truncate to cordate, apex obtuse to acute.
continuous, secund, (3–)6–26(–30) cm, axis glabrous or puberulent, verticillasters (3–)5–12, cymes 2–4-flowered, 2 per node;
proximal bracts ovate to lanceolate, 14–100 × 2–36 mm;
peduncles and pedicels glabrous or puberulent, peduncles to 71 mm, pedicels 4–14 mm.
calyx lobes ovate to orbiculate, 2–11 × 1.3–5.5 mm, glabrous or puberulent;
corolla blue to violet, with reddish purple nectar guides, ventricose, 24–48 mm, glabrous externally, glabrous internally or sparsely to moderately white-lanate internally abaxially, tube 5–12 mm, throat gradually inflated, slightly constricted at orifice, 8–13(–18) mm diam., rounded abaxially;
stamens included or longer pair reaching orifice, pollen sacs divergent, navicular, 1.4–2.5(–2.8) mm, dehiscing incompletely, connective not splitting, sides sparsely to moderately hirsute, hairs white or tan, to 0.5 mm, rarely glabrous, sutures denticulate, teeth to 0.2 mm;
staminode (15–)18–22 mm, included or barely exserted, 0.6–1.3 mm diam., tip straight to recurved, rounded to distinctly bifurcate at apex, glabrous or distal 1–2 mm sparsely lanate, hairs pale yellow, to 1.5 mm;
style 18–20 mm.
calyx lobes ovate, 3.8–9.5 × 1.3–3.3 mm, apex long-acuminate;
corolla 24–35 mm, sparsely to moderately white-lanate internally abaxially;
staminode apex rounded or bifurcate.
10–17 × 5–8 mm.
= 16.
Penstemon glaber
Penstemon glaber var. alpinus
Varieties 3 (3 in the flora).
The Penstemon glaber complex has been treated with as many as four species (F. W. Pennell 1920b) or one variable species as treated herein. M. K. W. Latady (1985) found clinal variation in most morphologic characters used to distinguish taxa in the complex and recognized only one species and two varieties: var. glaber (including var. alpinus) in the plains and mountains from southeastern Montana south to central Colorado; and var. brandegeei, in the mountains from central Colorado south to north-central New Mexico. A case for recognizing var. alpinus, as is done here, can be made on morphological, phenological, and ecological grounds.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Variety alpinus occurs in the Front Range of the Rocky Mountains on gravelly, granitic slopes, and roadcuts. The type of Penstemon magnus Pennell, on which P. alpinus subsp. magnus is based, was collected in Jackson County, Colorado. The specimen is in poor condition but has calyx lobes to 8 mm with apices short- to long-acuminate; it is tentatively assigned here.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
1. Calyx lobes 2–4.8 mm, apices rounded or abruptly short-acuminate; staminode apices rounded. | var. glaber |
1. Calyx lobes 3.8–11 mm, apices long-acuminate; staminode apices rounded or bifurcate. | → 2 |
2. Staminode apices rounded or bifurcate; corollas 24–35 mm; stems glabrous or puberulent proximally. | var. alpinus |
2. Staminode apices usually bifurcate; corollas 27–48 mm; stems puberulent to pubescent proximally. | var. brandegeei |
PNW Herbaria
WildflowerSearch
iNaturalist
USDA Plants Database
