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lilac beardtongue, lilac penstemon, slender beardtongue, slender penstemon

Panamint beardtongue, Panamint penstemon, rose penstemon

Habit Herbs. Herbs.
Caudex

herbaceous.

Stems

ascending to erect, (15–)20–50 cm, retrorsely hairy and glandular-pubescent, not glaucous.

ascending or erect, 50–120 cm, glaucous.

Leaves

basal and cauline, not leathery, glabrous or sparsely, rarely densely, puberulent;

basal and proximal cauline 25–75 × 4–15 mm, blade ovate to oblanceolate or lanceolate, base tapered, margins subentire or ± serrate, apex obtuse to acute;

cauline 4–7 pairs, sessile, 25–80(–90) × (2–)4–10(–15) mm, blade lanceolate to linear, base truncate to clasping, margins entire or serrulate to serrate, apex acute to acuminate.

basal and proximal cauline 45–80(–100) × 15–30(–40) mm, blade obovate to ovate, oblanceolate, or lanceolate, base tapered, margins coarsely dentate, apex obtuse to acute;

cauline 6–9 pairs, sessile or proximals short-petiolate, 50–100 × (8–)20–45 mm, blade ovate to lanceolate, base cordate-clasping or tapered, margins coarsely dentate, apex acute, sometimes obtuse.

Thyrses

interrupted, sometimes continuous, cylindric, (3–)5–17(–21) cm, axis glandular-pubescent, verticillasters (2 or)3–5(–7), cymes 2–6-flowered, 2 per node;

proximal bracts lanceolate, 5–95 × 1–12 mm, margins entire or serrulate, rarely serrate;

peduncles and pedicels ascending to erect, glandular-pubescent.

interrupted, secund, 30–80 cm, axis glabrous or sparsely glandular-pubescent distally, verticillasters 9–19, cymes 1–5-flowered;

proximal bracts lanceolate, 10–55 × 2–30 mm;

peduncles and pedicels ascending to erect, glandular-pubescent.

Flowers

calyx lobes ovate to lanceolate, 4–6 × 1.5–2 mm, glandular-pubescent;

corolla light lavender to lavender, with violet nectar guides, tubular, 14–22 mm, glandular-pubescent externally, moderately white-pilose internally abaxially, tube 4–6 mm, throat slightly inflated, 4–6 mm diam., prominently 2-ridged abaxially;

stamens included, pollen sacs divergent, navicular, 1–1.3 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 11–12 mm, reaching orifice, 0.4–0.5 mm diam., tip slightly recurved, distal 7–9 mm densely villous, hairs golden yellow, to 1.5 mm;

style 9–12 mm.

calyx lobes ovate, 4.2–6 × 2–3 mm, glandular-pubescent;

corolla lavender to light pink, rose pink, or light yellow, with reddish nectar guides, strongly bilabiate, ventricose, 21–32 mm, glandular-pubescent externally, glandular-pubescent internally, tube 6–12 mm, length 2–2.2 times calyx lobes, throat gradually to abruptly inflated, constricted or slightly so at orifice, 6–16 mm diam., rounded abaxially;

stamens included, filaments glabrous, pollen sacs explanate, 1.4–1.8 mm, sutures smooth;

staminode 16–19 mm, included, 0.7–0.9 mm diam., tip straight, glabrous;

style 15–20 mm, glabrous.

Capsules

6–8 × 3–4 mm, glabrous.

8–13 × 4–7 mm, glabrous.

2n

= 16.

= 16.

Penstemon gracilis

Penstemon floridus

Phenology Flowering May–Aug.
Habitat Tallgrass, mixed grass, and shortgrass prairies, foothills.
Elevation 300–2100 m. (1000–6900 ft.)
Distribution
from FNA
CO; IA; IL; IN; MI; MN; MT; ND; NE; NM; SD; WI; WY; AB; BC; MB; ON; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Glabrous-leaved plants are characteristic on the prairies of most of the central and northern Great Plains, and in the foothills of the Central, Northern, and Canadian Rocky mountains. Puberulent-leaved plants from the Driftless Area of Wisconsin have been named var. wisconsinensis. Puberulent-leaved plants also occur in Alberta and in North Dakota (specimens from Barnes, Benton, Eddy, Pierce, Ramsey, Wells, and Williams counties have been seen), sometimes with glabrous-leaved plants. Penstemon gracilis is introduced in Indiana (K. Yatskievych 2000).

The roots of Penstemon gracilis are used by the Lakota of the northern Great Plains for protection from snakebites (D. E. Moerman 1998).

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

Varieties 2 (2 in the flora).

The two varieties of Penstemon floridus are sympatric in the southern Silver Peak Range and southern White Mountains, where they apparently hybridize and introgress (N. H. Holmgren 1984).

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

Key
1. Corollas 24–32 mm, tubes 7–12 mm, throats abruptly inflated, constricted at orifices, (10–)11–16 mm diam.
var. floridus
1. Corollas 21–27 mm, tubes 6–9 mm, throats gradually inflated, slightly constricted at orifices, 6–10(–11) mm diam.
var. austinii
Source FNA vol. 17, p. 205. FNA vol. 17, p. 249.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles
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. 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. 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. 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. floridus var. austinii, P. floridus var. floridus
Synonyms P. gracilis subsp. wisconsinensis, P. gracilis var. wisconsinensis
Name authority Nuttall: Gen. N. Amer. Pl. 2: 52. (1818) — (as Pentstemon gracile) Brandegee: Bot. Gaz. 27: 454. (1899)
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