The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

sawsepal penstemon, southern smooth beardtongue, western smooth beardtongue

mucronate penstemon, sheep creek beardtongue

Stems

ascending, (10–)50–65(–80) cm, glabrous or puberulent to pubescent, not glaucous.

ascending to erect, 10–35(–46) cm, glabrous.

Leaves

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.

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

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.

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 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–)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

10–17 × 5–8 mm.

8–10 × 6–7 mm.

2n

= 16.

Penstemon glaber

Penstemon mucronatus

Phenology Flowering May–Jun.
Habitat Sandy or gravelly soils, juniper and pinyon-juniper woodlands.
Elevation 1500–2500 m. (4900–8200 ft.)
Distribution
from FNA
CO; MT; ND; NE; NM; SD; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; UT; WY
[WildflowerSearch map]
Discussion

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.)

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.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
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
Source FNA vol. 17, p. 167. FNA vol. 17, p. 121.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei
Sibling taxa
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, P. grandiflorus, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. humilis, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. mucronatus, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
P. abietinus, P. absarokensis, P. acaulis, P. acuminatus, P. alamosensis, P. albertinus, P. albidus, P. albomarginatus, P. ambiguus, P. ammophilus, P. anguineus, P. angustifolius, P. arenarius, P. arenicola, P. aridus, P. arkansanus, P. attenuatus, P. atwoodii, P. auriberbis, P. australis, P. azureus, P. baccharifolius, P. barbatus, P. barnebyi, P. barrettiae, P. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, P. caespitosus, P. calcareus, P. californicus, P. calycosus, P. canescens, P. cardinalis, P. cardwellii, P. carnosus, P. caryi, P. centranthifolius, P. cinicola, P. clevelandii, P. clutei, P. cobaea, P. comarrhenus, P. compactus, P. concinnus, P. confertus, P. confusus, P. crandallii, P. cusickii, P. cyananthus, P. cyaneus, P. cyanocaulis, P. cyathophorus, P. dasyphyllus, P. davidsonii, P. deamii, P. deaveri, P. debilis, P. degeneri, P. deustus, P. digitalis, P. diphyllus, P. discolor, P. dissectus, P. distans, P. dolius, P. duchesnensis, P. eatonii, P. elegantulus, P. ellipticus, P. eriantherus, P. euglaucus, P. fendleri, P. filiformis, P. flavescens, P. floribundus, P. floridus, P. flowersii, P. franklinii, P. fremontii, P. fruticiformis, P. fruticosus, P. gairdneri, P. gibbensii, P. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, P. grandiflorus, P. griffinii, P. grinnellii, P. guadalupensis, P. hallii, P. harbourii, P. harringtonii, P. havardii, P. haydenii, P. heterodoxus, P. heterophyllus, P. hirsutus, P. humilis, P. idahoensis, P. immanifestus, P. incertus, P. inflatus, P. jamesii, P. janishiae, P. kingii, P. kralii, P. labrosus, P. laetus, P. laevigatus, P. laevis, P. lanceolatus, P. laricifolius, P. laxiflorus, P. laxus, P. leiophyllus, P. lemhiensis, P. lentus, P. leonardii, P. linarioides, P. longiflorus, P. lyallii, P. marcusii, P. mensarum, P. metcalfei, P. miser, P. moffatii, P. monoensis, P. montanus, P. moriahensis, P. multiflorus, P. murrayanus, P. nanus, P. navajoa, P. neomexicanus, P. neotericus, P. newberryi, P. nitidus, P. nudiflorus, P. oklahomensis, P. oliganthus, P. ophianthus, P. osterhoutii, P. ovatus, P. pachyphyllus, P. pahutensis, P. pallidus, P. palmeri, P. papillatus, P. parryi, P. parvulus, P. parvus, P. patens, P. payettensis, P. paysoniorum, P. peckii, P. penlandii, P. pennellianus, P. perpulcher, P. personatus, P. petiolatus, P. pinifolius, P. pinorum, P. platyphyllus, P. pratensis, P. procerus, P. pruinosus, P. pseudoputus, P. pseudospectabilis, P. pudicus, P. pumilus, P. purpusii, P. putus, P. radicosus, P. rattanii, P. retrorsus, P. rhizomatosus, P. richardsonii, P. roezlii, P. rostriflorus, P. rubicundus, P. rupicola, P. rydbergii, P. saxosorum, P. scapoides, P. scariosus, P. secundiflorus, P. seorsus, P. sepalulus, P. serrulatus, P. smallii, P. spatulatus, P. speciosus, P. spectabilis, P. stenophyllus, P. stephensii, P. strictiformis, P. strictus, P. subglaber, P. subserratus, P. subulatus, P. sudans, P. superbus, P. tenuiflorus, P. tenuis, P. teucrioides, P. thompsoniae, P. thurberi, P. tidestromii, P. tiehmii, P. tracyi, P. triflorus, P. triphyllus, P. tubaeflorus, P. uintahensis, P. utahensis, P. venustus, P. virens, P. virgatus, P. wardii, P. washingtonensis, P. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Subordinate taxa
P. glaber var. alpinus, P. glaber var. brandegeei, P. glaber var. glaber
Synonyms P. pachyphyllus var. mucronatus
Name authority Pursh: Fl. Amer. Sept. 2: 738. (1813) — (as Pentstemon glabra) N. H. Holmgren: Brittonia 31: 234, fig. 10. (1979)
Web links