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sawsepal penstemon, southern smooth beardtongue, western smooth beardtongue

long-sepal beardtongue

Habit Herbs.
Stems

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

erect, (40–)60–120 cm, puberulent, at least proximally, slightly glaucous or not.

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, basal often withering by anthesis, not leathery, glabrous;

basal and proximal cauline 47–110 × 10–24 mm, blade oblanceolate, base tapered, margins entire or ± serrate, apex rounded to obtuse;

cauline 3–7 pairs, sessile or proximals short-petiolate, (14–)44–155 × (2–)13–46 mm, blade lanceolate to ovate, proximals sometimes oblanceolate, base clasping or tapered, margins serrate, 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, (5–)14–20 cm, axis sparsely puberulent and glandular-pubescent, rarely glabrous, verticillasters 2–5, cymes (1–)5–15-flowered, 2 per node;

proximal bracts ovate to lanceolate, sometimes linear, 13–80 × (2–)5–32 mm, margins serrate, sometimes entire;

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

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 lanceolate, 5–9 × 0.8–1.9 mm, apex acuminate, sparsely glandular-pubescent;

corolla pale lavender to violet, with faint violet nectar guides, ventricose, 20–35 mm, glandular-pubescent externally, ± white-pubescent internally abaxially, tube 5–7 mm, throat abruptly inflated, 8–11 mm diam., slightly 2-ridged abaxially;

stamens included or longer pair reaching orifice, pollen sacs opposite, navicular, 1.2–1.4 mm, dehiscing completely, connective splitting, sides glabrous, rarely sparsely pubescent, hairs white, to 0.2 mm, sutures papillate;

staminode 11–13 mm, reaching orifice, 0.2–0.3 mm diam., tip straight to slightly recurved, distal 2–5 mm sparsely pubescent, hairs yellowish, to 1 mm;

style 14–16 mm.

Capsules

10–17 × 5–8 mm.

7–8 × 4–5 mm, glabrous.

2n

= 96.

Penstemon glaber

Penstemon calycosus

Phenology Flowering May–Jun.
Habitat Woodlands, meadows, rocky slopes, stream banks.
Elevation 10–300 m. (0–1000 ft.)
Distribution
from FNA
CO; MT; ND; NE; NM; SD; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; CT; DC; GA; IL; IN; KY; MA; MD; ME; MI; MN; MO; NC; NJ; NY; OH; PA; RI; SC; TN; VA; VT; ON
[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 calycosus is concentrated in the Central Lowlands and Interior Low Plateaus; occurrences farther south and east, especially in New England, may be from introductions (F. W. Pennell 1935). The range lies almost entirely within that of P. digitalis, but historic ranges of both P. calycosus and P. digitalis are difficult to delimit due to both past and continuing introduction and spread of both species. Calyx lobe lengths to 12 mm are reported in the literature; those appear to be from fruiting calyces. Penstemon calycosus usually has glabrous anthers, but many specimens, especially from Illinois and Ohio, bear hairs on the adaxial surfaces of the anthers. Some populations from this region exhibit variation in vegetative (leaf size and bract shape and margins) and floral characters (calyx lobe shape and size, corolla color, and anther pubescence), suggesting possible hybridization with P. digitalis, an observation that would be consistent with the findings of A. C. Koelling (1964).

(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. 197.
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. 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. 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
Name authority Pursh: Fl. Amer. Sept. 2: 738. (1813) — (as Pentstemon glabra) Small: Bull. Torrey Bot. Club 25: 470. (1898) — (as Pentstemon)
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