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sawsepal penstemon, southern smooth beardtongue, western smooth beardtongue

eastern white-flower beardtongue

Habit Herbs.
Stems

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

ascending to erect, 20–80 cm, retrorsely hairy and ± glandular-lanate, retrorse hairs sometimes few or distal only, not glaucous.

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, not leathery, moderately to densely glandular-lanate, especially along major veins abaxially;

basal and proximal cauline 40–138 × 7–37 mm, blade spatulate to oblanceolate or elliptic, base tapered, margins entire or ± serrate to dentate, apex rounded to obtuse or acute;

cauline 4–7 pairs, sessile or proximals sometimes petiolate, (11–)20–110 × 3–30(–40) mm, blade ovate to lanceolate, base truncate to clasping, sometimes tapered, margins entire or crenate-serrate to dentate, apex acute to acuminate.

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, conic, (3–)8–37 cm, axis moderately to densely glandular-pubescent to glandular-lanate, verticillasters 3–6(or 7), cymes 3–10(–13)-flowered, 2 per node;

proximal bracts lanceolate, 6–40 × 1–10 mm, margins entire or ± serrate;

peduncles and pedicels ascending, moderately to densely glandular-pubescent to glandular lanate.

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 to broadly lanceolate, 2–5 × 1.3–2 mm, glandular-pubescent;

corolla white, without nectar guides, personate, tubular, 21–28 mm, sparsely glandular-pubescent externally, moderately to densely white-villous internally abaxially, tube 6–8 mm, throat slightly inflated, 5–8 mm diam., 2-ridged abaxially;

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

staminode 13–16 mm, exserted, 0.4–0.6 mm diam., tip straight, distal 10–12 mm moderately to densely pubescent, hairs yellow, to 1.6 mm;

style 16–19 mm.

Capsules

10–17 × 5–8 mm.

5–7 × 3–5 mm, glabrous.

Penstemon glaber

Penstemon tenuiflorus

Phenology Flowering Apr–Jun.
Habitat Dry woods, cedar glades, prairies, barrens, cliffs.
Elevation 30–80 m. (100–300 ft.)
Distribution
from FNA
CO; MT; ND; NE; NM; SD; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; KY; MS; TN
[WildflowerSearch map]
[BONAP county 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 tenuiflorus is concentrated in the Interior Low Plateaus region of western Kentucky, central Tennessee, and northwestern Alabama, and in the Black Belt subsection of the Coastal Plain of central Alabama and northeastern Mississippi.

R. K. Clements et al. (1998) observed that the leaves of Penstemon tenuiflorus bear both simple and stellate hairs, reporting only simple hairs on the leaves of closely related P. hirsutus. However, stellate hairs occur in the leaf axils of plants in some populations of P. hirsutus, and they are common on the stems. Stellate hairs also occur on other diploid, tubular-flowered eastern North American species, including P. arkansanus, P. australis, P. brevisepalus, P. canescens, P. laxiflorus, P. oklahomensis, and P. pallidus. Stellate hairs have not been observed on any of the polyploid, ventricose-flowered eastern North American species.

(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. 223.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
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. 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. 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
Name authority Pursh: Fl. Amer. Sept. 2: 738. (1813) — (as Pentstemon glabra) Pennell: Addisonia 4: 79, plate 160. (1919)
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