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eastern white beardtongue, pale beardtongue, pale penstemon

Charleston beardtongue, smoothleaf beardtongue, smoothleaf penstemon

Habit Herbs.
Stems

ascending to erect, 25–55(–65) cm, retrorsely hairy and glandular-villous proximally, retrorsely hairy and glandular-pubescent distally, glandular hairs sometimes sparse, not glaucous.

ascending to erect, 4–55(–80) cm, glabrous, not glaucous.

Leaves

basal and cauline, basal often withering by anthesis, not leathery, sparsely to densely pubescent, sometimes also with scattered glandular hairs, abaxially, sparsely pubescent adaxially;

basal and proximal cauline 20–120(–180) × 5–35(–40) mm, blade spatulate to obovate or ovate, base tapered, margins subentire or ± serrate or dentate, apex rounded to obtuse or acute;

cauline 4–8 pairs, sessile, 22–100 × 4–24 mm, blade ovate to lanceolate, base truncate to clasping, margins subentire or ± serrate or dentate, apex acute to acuminate.

basal and cauline, not leathery, glabrous, not glaucous;

basal and proximal cauline (20–)30–100 × 4–15(–20) mm, blade oblanceolate, base tapered, margins entire, apex obtuse to acute;

cauline 2–7 pairs, sessile or proximals sometimes short-petiolate, 16–80 × 2–20 mm, blade lanceolate to linear, base tapered, apex obtuse to acute.

Thyrses

interrupted, conic, 5–26(–30) cm, axis sparsely to densely glandular-pubescent, verticillasters 3–8, cymes 2–8(–16)-flowered, 2 per node;

proximal bracts lanceolate, 7–72 × 2–22 mm, margins entire or ± dentate;

peduncles and pedicels ascending, sparsely to densely glandular-pubescent.

interrupted or continuous, secund, (1–)3–30(–40) cm, axis glandular-pubescent, verticillasters 2–8(–12), cymes 1–3(or 4)-flowered, (1 or)2 per node;

proximal bracts lanceolate, (6–)10–60 × (1–)3–24 mm;

peduncles and pedicels glandular-pubescent.

Flowers

calyx lobes ovate to lanceolate, (2–)3–5 × 1–3 mm, sparsely glandular-pubescent;

corolla white, sometimes tinged lavender or blue, with reddish purple nectar guides, tubular to tubular-funnelform, 16–22 mm, glandular-pubescent externally, moderately whitish or yellowish lanate internally abaxially, tube 4–6 mm, throat slightly inflated, 4–7 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, (0.8–)1–1.2 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, exserted, 0.2–0.3 mm diam., tip straight to slightly recurved, distal 8–9 mm moderately to densely villous, hairs yellow or golden yellow, to 1.5 mm;

style 12–14 mm.

calyx lobes lanceolate, (3.8–)4.5–8.5 × 1.6–3.8 mm, glandular-pubescent;

corolla violet to blue or purple, with violet or reddish purple nectar guides, ventricose, 18–35 mm, glandular-pubescent externally, glabrous or white-lanate internally abaxially, glandular-pubescent adaxially, tube 6–10 mm, throat gradually inflated, not constricted at orifice, 5–10 mm diam., 2-ridged abaxially;

stamens: longer pair reaching orifice, pollen sacs divergent to nearly opposite, navicular, 1.2–2 mm, dehiscing incompletely, proximal 1/5 indehiscent, connective not splitting, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 10–14 mm, included, 0.4–0.5 mm diam., tip straight, distal 1–5 mm sparsely to densely pilose, hairs yellow or orangish yellow, to 1 mm;

style 12–19 mm.

Capsules

5–7 × 3–5 mm, glabrous.

7–11 × 5–6 mm.

2n

= 16.

Penstemon pallidus

Penstemon leiophyllus

Phenology Flowering Apr–Jun(–Jul).
Habitat Tallgrass prairie, limestone and sandstone glades, barrens, rocky oak-hickory woodlands.
Elevation 10–300 m. (0–1000 ft.)
Distribution
from FNA
AL; AR; CT; DC; GA; IA; IL; IN; KS; KY; MA; MD; ME; MI; MN; MO; NC; NH; NJ; NY; OH; PA; RI; TN; VA; VT; WI; WV; ON
[WildflowerSearch map]
[BONAP county map]
from FNA
NV; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon pallidus is concentrated in the Central Lowlands and Ozark Plateau of the central United States. F. W. Pennell (1935) believed it to be native there, having spread eastward as a result of human activities, as in Ontario.

Penstemon brevisepalus, which has been synonymized with P. pallidus by many authors, is treated here as a distinct species. Characters distinguishing the species are discussed under 147. P. brevisepalus.

Some specimens from north-central Arkansas and north-central Missouri are morphologically intermediate between Penstemon pallidus and P. arkansanus.

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

Varieties 3 (3 in the flora).

F. S. Crosswhite (1967) recognized three species in the Penstemon leiophyllus complex: P. francisci-pennellii, P. keckii, and P. leiophyllus. N. H. Holmgren (1984) expanded P. leiophyllus to include the other species as varieties. The complex is unique in the section in having patches of glandular hairs on the internal, adaxial surfaces of the corolla throats. The varieties are essentially allopatric; characters distinguishing them are minor.

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

Key
1. Stems 15–55(–80) cm; cauline leaves 4–20 mm wide, blades lanceolate, usually flat and straight; corollas glabrous, rarely white-lanate, internally abaxially; Utah.
var. leiophyllus
1. Stems 4–25(–43) cm; cauline leaves 2–5(–10) mm wide, blades lanceolate to linear, usually folded lengthwise and curved; corollas white-lanate, rarely glabrous, internally abaxially; Nevada.
→ 2
2. Corollas (22–)25–35 mm; Lincoln, Nye, and White Pine counties, Nevada.
var. francisci-pennellii
2. Corollas 18–22 mm; Clark County, Nevada.
var. keckii
Source FNA vol. 17, p. 214. FNA vol. 17, p. 170.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri
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. 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. 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. 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. 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
Subordinate taxa
P. leiophyllus var. francisci-pennellii, P. leiophyllus var. keckii, P. leiophyllus var. leiophyllus
Name authority Small: Fl. S.E. U.S., 1060, 1337. (1903) — (as Pentstemon) Pennell: Contr. U.S. Natl. Herb. 20: 346. (1920)
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