Penstemon mucronatus

N. H. Holmgren

Brittonia 31: 234, fig. 10. 1979.

Common names: Sheep Creek beardtongue
Endemic
Synonyms: Penstemon pachyphyllus var. mucronatus (N. H. Holmgren) Neese
Treatment appears in FNA Volume 17. Treatment on page 121. Mentioned on page 111, 123.

Stems ascending to erect, 10–35 (–46) cm, glabrous. Leaves basal and cauline, glabrous; basal and proximal cauline 23–65 (–100) × (9–) 13–40 mm, blade oblanceolate, base tapered, apex rounded to obtuse or acute; cauline (2–) 4–6 (–9) pairs, sessile, (8–) 20–30 × 8–26 mm, blade ovate to orbiculate, base clasping, apex mucronate. Thyrses interrupted, cylindric, (2–) 11–18 (–27) cm, axis glabrous, verticillasters 6–9 (–15), cymes 2–6-flowered; proximal bracts orbiculate to ovate, 7–28 × 3–26 mm; peduncles and pedicels glabrous. Flowers: calyx lobes ovate, (3–) 4.5–6.5 × 1.5–2.3 mm, margins entire or erose, broadly scarious, glabrous; corolla blue to violet, with reddish violet nectar guides, guides sometimes passing onto limb, tubular-funnelform, (10–) 13–17 (–20) mm, glabrous externally, sparsely white-villous internally abaxially, tube (5–) 7–10 mm, throat gradually inflated, 4.5–5.5 (–7) mm diam., rounded abaxially; stamens included or longer pair reaching orifice, pollen-sacs divergent to opposite, 0.7–1.1 mm, sutures papillate; staminode 7–13 mm, reaching orifice, (0.6–) 0.9–1.9 mm diam., tip strongly recurved, distal 2–5 mm moderately to densely pilose, hairs brownish yellow or golden yellow, to 1 mm; style (7–) 9–12 mm. Capsules 8–10 × 6–7 mm. 2n = 16.


Phenology: Flowering May–Jun.
Habitat: Sandy or gravelly soils, juniper and pinyon-juniper woodlands.
Elevation: 1500–2500 m.

Discussion

Penstemon mucronatus is known from Moffat and Rio Blanco counties, Colorado, Daggett and Uintah counties, Utah, and Carbon and Sweetwater counties, Wyoming. E. C. Neese (1993) considered it transitional to P. pachyphyllus var. pachyphyllus in northeastern Utah and treated it as a variety of that species. The two taxa often have similar leaf morphologies; P. mucronatus usually is easily distinguished from P. pachyphyllus var. pachyphyllus by its narrower staminode bearing shorter, less tangled hairs at the apex and nectar guides that extend onto the corolla limbs. Flowers of P. mucronatus are in many respects more similar to those of P. osterhoutii than they are to those of P. pachyphyllus. A chromosome count reported for P. pachyphyllus by F. S. Crosswhite and S. Kawano (1965) is referable to P. mucronatus.

Selected References

None.

Lower Taxa

None.

"/4+timescorollathroat" is not declared as a valid unit of measurement for this property.

... more about "Penstemon mucronatus"
mucronate +, rounded +  and obtuse or acute +
Craig C. Freeman +
N. H. Holmgren +
glutinous +
alternate +, opposite +, whorled +, helical +  and subopposite +
tapered +
ovate;orbiculate +
not +  and leathery +
0.3 cm3 mm <br />0.003 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
4.5mm;6.5mm +
1.5mm;2.3mm +
short-tubular +  and short-campanulate +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2 cm20 mm <br />0.02 m <br />) +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
Sheep Creek beardtongue +
not personate +  and bilabiate +
blue +  and violet +
hairy +, glabrous +  and glandular +
tubular-salverform +, ventricose +  and tubular-funnelform +
ampliate +
2-6-flowered +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
scale-like +  and not needlelike +
Colo. +, Utah +  and Wyo. +
drupe-like +
1500–2500 m. +
curved +  and straight +
1 +  and 4 +
1.7 cm17 mm <br />0.017 m <br /> (2 cm20 mm <br />0.02 m <br />) +
white-villous +  and glabrous +
tubular-funnelform +
1.3 cm13 mm <br />0.013 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
Sandy or gravelly soils, juniper and pinyon-juniper woodlands. +
golden yellow +  and brownish yellow +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
membranous +
terminal +  and axillary +
persistent +  and deciduous +
basal +  and cauline +
orbiculate;linear;orbiculate;linear;truncate;oblanceolate;obovate;oblong;elliptic;round;lanceolate;ovate +
erose +  and entire +
glutinous +
toothed +  and entire +
axile +  and parietal +
basal +, apical +  and superior +
tenuinucellate +, unitegmic +  and hemitropous +
campylotropous +, hemianatropous +  and anatropous +
ascending +  and erect +
ascending;erect +
5 +  and 4 +
Flowering May–Jun. +
divergent +  and opposite +
navicular-sigmoid +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.11 cm1.1 mm <br />0.0011 m <br />) +
0.7 cm7 mm <br />0.007 m <br /> (2.8 cm28 mm <br />0.028 m <br />) +
orbiculate +  and ovate +
0.3 cm3 mm <br />0.003 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
minute +
dark-brown +  and brown +
disciform +, angled-elongate +  and angled +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.54 cm5.4 mm <br />0.0054 m <br />) +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
included +  and exserted +
0.7 cm7 mm <br />0.007 m <br /> (?) +  and 1.3 cm13 mm <br />0.013 m <br /> (?) +
short-petiolate +  and petiolate +
35 cm350 mm <br />0.35 m <br /> (46 cm460 mm <br />0.46 m <br />) +
climbing +  and scrambling +
sprawling +, creeping +  and prostrate +
ascending;erect +
cauline +, proximal +  and basal +
reduced +
10 cm100 mm <br />0.1 m <br /> (35 cm350 mm <br />0.35 m <br />) +
leathery +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
papillate +
denticulate +
Penstemon pachyphyllus var. mucronatus +
Penstemon mucronatus +
Penstemon sect. Coerulei +
species +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.55 cm5.5 mm <br />0.0055 m <br />) +
rounded +  and inflated +
not constricted +
18 cm180 mm <br />0.18 m <br /> (27 cm270 mm <br />0.27 m <br />) +
cylindric +
11 cm110 mm <br />0.11 m <br /> (18 cm180 mm <br />0.18 m <br />) +
straight +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
gibbous +  and not spurred +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
short-petiolate +  and sessile +
cauline +  and proximal +