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large beardtongue, largeflower penstemon, shell-leaf beardtongue

Habit Herbs.
Stems

glabrous, sometimes scabrous, glaucous.

erect, (40–)50–95(–120) cm, glabrous.

Leaves

basal and cauline, sometimes basal absent or reduced, opposite, leathery, glabrous, rarely scabrous, glaucous;

basal and proximal cauline petiolate, sometimes short-petiolate (P. immanifestus, P. lentus);

cauline sessile, sometimes short-petiolate, blade obovate, ovate, spatulate, trullate, oblanceolate, lanceolate, oblong, elliptic, linear, or orbiculate, margins entire.

basal and cauline, glabrous;

basal and proximal cauline 30–160 × 6–50 mm, blade spatulate to obovate, base tapered, apex rounded to obtuse or acute;

cauline 4–8 pairs, sessile, 18–90(–110) × 15–50 mm, blade spatulate to orbiculate, base clasping, apex rounded to obtuse.

Thyrses

continuous or interrupted, cylindric, sometimes secund, axis glabrous, rarely scabrous or glutinous, cymes 2 per node;

peduncles and pedicels ascending to erect.

interrupted, cylindric, 12–30(–40) cm, axis glabrous, verticillasters 3–7(–9), cymes 2–4-flowered;

proximal bracts ovate to elliptic or orbiculate, (9–)16–83 × (9–)16–54 mm;

peduncles and pedicels glabrous.

Flowers

calyx lobes: margins entire or erose, herbaceous or ± scarious, glabrous, rarely scabrous, glandular, glandular-pubescent, or glutinous;

corolla lavender to blue, violet, purple, or pink, rarely white or red, bilaterally symmetric, rarely nearly radially symmetric (P. cyathophorus), weakly, rarely strongly, bilabiate, not personate, tubular-funnelform, funnelform, or weakly ventricose, rarely tubular-salverform or weakly ampliate, glabrous externally, rarely obscurely glandular, glabrous or hairy internally abaxially, throat slightly to abruptly inflated, not constricted at orifice, rounded abaxially, rarely slightly 2-ridged;

stamens included to exserted, filaments glabrous, pollen sacs opposite, rarely divergent or parallel, navicular, rarely explanate (P. murrayanus), dehiscing completely, connective splitting, sides glabrous, sutures papillate, sometimes smooth;

staminode included to exserted, flattened distally, (0.2–)0.4–3 mm diam., tip recurved, rarely coiled or straight, distal 10–50(–70)% hairy, hairs to 2.5 mm, rarely glabrous;

style glabrous.

calyx lobes ovate to lanceolate, 7–11 × 2.5–4 mm, margins entire, rarely erose, herbaceous or narrowly scarious, glabrous;

corolla lavender to blue or pinkish blue, with magenta nectar guides, ampliate, 35–48 mm, glabrous externally, glabrous internally, tube 10–13 mm, throat abruptly inflated, 15–18 mm diam., rounded abaxially;

stamens included, pollen sacs opposite, 2.1–2.6 mm, sutures papillate;

staminode 16–21 mm, included or reaching orifice, 2–2.6 mm diam., tip recurved to coiled, distal 1–2 mm sparsely villous, hairs golden yellow, to 0.5 mm;

style 19–30 mm.

Capsules

glabrous.

16–20(–25) × 8–15 mm.

Seeds

brown or dark brown, angled, angled-elongate, or disciform, 1.8–5.4 mm.

2n

= 16.

Penstemon sect. Coerulei

Penstemon grandiflorus

Phenology Flowering Apr–Jul.
Habitat Sandy or calcareous soils, tallgrass, mixed-grass, and sand prairies.
Elevation 200–1800(–2400) m. (700–5900(–7900) ft.)
Distribution
North America; n Mexico
from FNA
CO; CT; IA; IL; IN; KS; MA; MI; MN; MO; MT; ND; NE; NM; OH; OK; SD; TX; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Species 20 (20 in the flora).

D. D. Keck (1951) proposed the section name Anularius for sect. Coerulei, believing that the name of Pennell was invalid. N. H. Holmgren (1979b) concluded that the section names of Pennell are valid and that sect. Anularius Keck is invalid; the new combinations by Keck in that publication lacked descriptions.

Members of sect. Coerulei usually are recognized by their mostly glabrous, glaucous, and fleshy herbage, their blue or pink corollas that are glabrous, rarely obscurely glandular, externally, and their relatively broad and heavily bearded staminodes. Penstemon murrayanus has red corollas and glabrous staminodes. Members of sect. Coerulei mostly occur on well-drained, sandy soils. Molecular data (C. A. Wessinger et al. 2016) support the monophyly of the section.

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

Widely distributed in the western Midwest and Great Plains in the United States, Penstemon grandiflorus is cultivated as an ornamental for its showy flowers. Reports from Connecticut (D. W. Magee and H. E. Ahles 2007), Indiana (K. Yatskievych 2000), Massachusetts (Magee and Ahles), Michigan (E. G. Voss 1972–1996), and Ohio (T. S. Cooperrider 1995) appear to be based on introductions. Penstemon grandiflorus has been seeded along highways in Iowa and Nebraska, where it is also native.

The validity of the name Penstemon grandiflorus has been debated owing to the meager diagnosis by Nuttall. The name is accepted here, making P. bradburyi Pursh, an illegitimate, superfluous replacement for P. grandiflorus.

The Dakota, Kiowa, and Sioux tribes, centered in the Great Plains, use Penstemon grandiflorus as an analgesic, a gastrointestinal aid, and for fevers (D. E. Moerman 1998).

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

Key
1. Corollas red; staminodes glabrous; pollen sacs explanate.
P. murrayanus
1. Corollas lavender to blue, violet, purple, or pink, rarely white; staminodes hairy; pollen sacs navicular.
→ 2
2. Pollen sacs parallel or divergent; stamens: 2 or 4 prominently exserted; corollas without nectar guides.
→ 3
3. Stamens: 4 exserted; pollen sacs 1.2–1.5 mm; corollas 11–14 mm.
P. cyathophorus
3. Stamens: 2 exserted; pollen sacs 2–3 mm; corollas 17–24 mm.
P. harringtonii
2. Pollen sacs opposite or divergent; stamens included or longer pair reaching orifice to slightly exserted; corollas usually with nectar guides.
→ 4
4. Corollas 21–48 mm, ampliate, glabrous internally, throats abruptly inflated.
→ 5
5. Corollas 35–48 mm; cauline leaf blades spatulate to orbiculate.
P. grandiflorus
5. Corollas 21–28 mm; cauline leaf blades lanceolate to linear.
P. haydenii
4. Corollas 10–25(–28) mm, tubular-funnelform, tubular-salverform, funnelform, or ventricose, white-villous internally abaxially or glabrous, throats not abruptly inflated.
→ 6
6. Corollas tubular-salverform; thyrses interrupted.
P. fendleri
6. Corollas tubular-funnelform, funnelform, or ventricose; thyrses continuous or interrupted.
→ 7
7. Stems 3–10(–15) cm; cauline leaf pairs 1–3; thyrses 1–6 cm; verticillasters 1–5(or 6).
P. bracteatus
7. Stems (4–)7–77(–82) cm; cauline leaf pairs 1–8(or 9); thyrses (2–)3–37(–57) cm; verticillasters (2 or)3–20(–35).
→ 8
8. Thyrses secund.
→ 9
9. Cauline leaves 2–4 pairs; staminodes 8–9 mm, distal 3–4 mm sparsely to densely villous, hairs yellowish, to 1 mm; Arizona, Colorado, New Mexico, Utah.
P. lentus
9. Cauline leaves 4–6 pairs; staminodes 10–13 mm, distal 4–6 mm densely villous, hairs golden yellow, to 2 mm; Colorado, New Mexico, Wyoming.
P. secundiflorus
8. Thyrses cylindric.
→ 10
10. Staminodes 2–3 mm diam.; corollas with nectar guides, sparsely to moderately white-villous internally abaxially, rarely glabrous.
P. osterhoutii
10. Staminodes (0.2–)0.4–2 mm diam.; corollas with or without nectar guides, glabrous or sparsely white-villous internally abaxially.
→ 11
11. Corollas pink or white.
→ 12
12. Corollas white.
P. lentus
12. Corollas pink.
→ 13
13. Leaves: basal usually reduced or absent; corollas glabrous internally; staminodes: distal 0.5–1.5 mm lanulose, hairs to 0.6 mm.
P. flowersii
13. Leaves: basal not reduced; corollas sparsely white-hairy internally abaxially or glabrous; staminodes: distal 2–6 mm villous, hairs to 1 mm.
→ 14
14. Cauline leaf apices acute to acuminate; corollas tubular-funnelform; calyx lobes ovate to lanceolate, 4–8 × 1–2.5 mm.
P. angustifolius
14. Cauline leaf apices obtuse to acute; corollas funnelform to ventricose; calyx lobes ovate, 5–8(–12) × 2–3.5 mm.
P. immanifestus
11. Corollas blue, pinkish blue, lavender-blue, lavender, violet, or purple, rarely some individuals with corollas pink.
→ 15
15. Cauline leaf blades ovate to orbiculate; corollas with nectar guides, villous internally abaxially.
P. mucronatus
15. Cauline leaf blades elliptic to ovate, obovate, lanceolate, oblanceolate, or linear; corollas with or without nectar guides, glabrous or villous internally abaxially.
→ 16
16. Stems decumbent to ascending, (4–)7–18(–30) cm; thyrses continuous; proximal bracts oblanceolate to lanceolate; corollas (10–)12–15 mm; pollen sacs 0.7–0.8 mm.
P. arenicola
16. Stems ascending to erect, (5–)9–60(–82) cm; thyrses interrupted or continuous; proximal bracts orbiculate to ovate, lanceolate, oblong, or linear; corollas 10–22 mm; pollen sacs 0.7–1.6 mm.
→ 17
17. Proximal bracts orbiculate to ovate; corollas lavender to bluish lavender or pinkish blue, glabrous internally; capsules 12–18(–20) mm.
P. buckleyi
17. Proximal bracts ovate to oblong, lanceolate, or linear, rarely orbiculate; corollas blue, pinkish blue, bluish lavender, violet, or purple, hairy internally abaxially or glabrous; capsules 7–15 mm.
→ 18
18. Corollas obscurely glandular externally or glabrous; cauline leaves 1–3 pairs; thyrses 3–15 cm, continuous, sometimes interrupted.
P. carnosus
18. Corollas glabrous externally; cauline leaves 2–8 pairs; thyrses (2–)5–30(–37) cm, continuous or interrupted.
→ 19
19. Staminodes 1–2 mm diam., distal 6–8 mm villous, hairs to 2.5 mm.
P. pachyphyllus
19. Staminodes (0.2–)0.5–1.5 mm diam., distal 1.5–7 mm pilose to villous, hairs to 1.5 mm.
→ 20
20. Cauline leaf blades: apices obtuse to acute, sometimes rounded or mucronate; peduncles to 12–28 mm; corolla throats 5–8 mm diam.
→ 21
21. Cymes 1–3(or 4)-flowered; cauline leaves sessile; seeds 3.5–5 mm.
P. lentus
21. Cymes (1 or)2–6-flowered; cauline leaves short-petiolate or sessile; seeds 2–4 mm.
→ 22
22. Corollas bluish lavender to lavender, 15–22 mm; peduncles to 12 mm; calyx lobes ovate, 5–8(–12) mm, apices acuminate; staminodes: distal 2–5 mm densely villous, hairs yellowish, brownish, or orangish, to 1 mm.
P. immanifestus
22. Corollas blue to violet, sometimes lavender, 12–20 mm; peduncles to 26 mm; calyx lobes ovate to lanceolate, (2.5–)4–7 mm, apices acute to acuminate or caudate; staminodes: distal 4–8 mm densely villous, hairs yellow to golden yellow, to 2.5 mm.
P. pachyphyllus
20. Cauline leaf blades: apices acute to acuminate, sometimes mucronate (P. nitidus); peduncles to 3–4 mm; corolla throats 4–6 mm diam.
→ 23
23. Cymes 2–5-flowered, verticillasters (2–)4–10; corolla tubes 4–6 mm; stems glabrous.
P. nitidus
23. Cymes (2–)4–8(–12)-flowered, verticillasters (3–)5–15(–26); corolla tubes 5–9 mm; stems glabrous or scabrous.
→ 24
24. Staminodes: distal 1.5–3.5 mm densely pilose, hairs to 0.6 mm; calyx lobes lanceolate, (3.2–)4.5–10 × 1.2–3.2(–3.8) mm; pollen sacs 0.7–1.3(–1.5) mm; Idaho, Nevada, Oregon, Washington.
P. acuminatus
24. Staminodes: distal 4–6 mm sparsely villous, hairs to 1 mm; calyx lobes ovate to lanceolate, 4–8 × 1–2.5 mm; pollen sacs (0.9–)1.1–1.5 mm; Arizona, Colorado, Kansas, Montana, Nebraska, New Mexico, North Dakota, Oklahoma, South Dakota, Utah, Wyoming.
P. angustifolius
Source FNA vol. 17, p. 110. FNA vol. 17, p. 118.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon 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. glaber, P. glandulosus, P. glaucinus, P. globosus, P. goodrichii, P. gormanii, P. gracilentus, P. gracilis, P. grahamii, 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
Subordinate taxa
P. acuminatus, P. angustifolius, P. arenicola, P. bracteatus, P. buckleyi, P. carnosus, P. cyathophorus, P. fendleri, P. flowersii, P. grandiflorus, P. harringtonii, P. haydenii, P. immanifestus, P. lentus, P. mucronatus, P. murrayanus, P. nitidus, P. osterhoutii, P. pachyphyllus, P. secundiflorus
Name authority Pennell: Contr. U.S. Natl. Herb. 20: 326, 331. (1920) Nuttall: Cat. Pl. Upper Louisiana, no. 64. (1813) — (as grandiflorum)
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