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sand dune penstemon, sand-dune beardtongue, sharp-leaf penstemon

long-sepal beardtongue

Habit Herbs.
Stems

ascending to erect, (9–)20–60 cm, glabrous or ± scabrous, especially distally.

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

Leaves

basal and cauline, glabrous, sometimes scabrous;

basal and proximal cauline (14–)30–95 × 4–15(–24) mm, blade oblanceolate to elliptic, base tapered, apex obtuse to acute or mucronate;

cauline (2 or)3–6(or 7) pairs, sessile, 18–60(–85) × (4–)8–28 mm, blade ovate to lanceolate, base tapered to cordate-clasping, apex acute to acuminate.

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 or interrupted, cylindric, 6–25(–30) cm, axis glabrous, rarely scabrous or glutinous, verticillasters (5–)7–15, cymes (2–)4–8(–12)-flowered;

proximal bracts ovate to lanceolate, 14–60 × 9–30 mm, margins entire, apex obtuse to acuminate or caudate;

peduncles and pedicels glabrous or scabrous, sometimes also glutinous, peduncles to 4 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 lanceolate, (3.2–)4.5–10 × 1.2–3.2(–3.8) mm, margins entire or erose, herbaceous or narrowly scarious, glabrous or scabrous proximally and, sometimes, along margins, sometimes also glutinous;

corolla blue to violet or purple, with reddish purple nectar guides, tubular-funnelform, 11–20 mm, glabrous externally, glabrous internally, tube 5–9 mm, throat gradually inflated, 4–6 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice to slightly exserted, pollen sacs opposite, navicular, 0.7–1.3(–1.5) mm, sutures papillate;

staminode 6–12 mm, reaching orifice, 0.6–1 mm diam., tip recurved, distal 1.5–3.5 mm densely pilose, hairs golden yellow, to 0.6 mm, hairs on proximal part of staminode mostly along margins;

style 8–15 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

7–13 × 4–7 mm.

7–8 × 4–5 mm, glabrous.

2n

= 96.

Penstemon acuminatus

Penstemon calycosus

Phenology Flowering May–Jun.
Habitat Woodlands, meadows, rocky slopes, stream banks.
Elevation 10–300 m. (0–1000 ft.)
Distribution
from FNA
ID; NV; OR; WA
[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 2 (2 in the flora).

Penstemon acuminatus includes the northern var. acuminatus, which has denser thyrses than the southern var. latebracteatus. Herbage of var. acuminatus is usually scabrous; herbage of var. latebracteatus is rarely scabrous.

The Blackfoot tribe of the Central Rocky Mountains use Penstemon acuminatus as an analgesic, antiemetic, and gastrointestinal aid (D. E. Moerman 1998).

(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. Styles 11–15 mm; corollas 14–20 mm; pollen sacs 0.8–1.3(–1.5) mm; calyx lobes 5–10 mm.
var. acuminatus
1. Styles 8–11 mm; corollas 11–15 mm; pollen sacs 0.7–1 mm; calyx lobes (3.2–)4.5–7 mm.
var. latebracteatus
Source FNA vol. 17, p. 113. FNA vol. 17, p. 197.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
Sibling taxa
P. abietinus, P. absarokensis, P. acaulis, 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. 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. acuminatus var. acuminatus, P. acuminatus var. latebracteatus
Name authority Douglas ex Lindley: Edwards’s Bot. Reg. 15: plate 1285. (1829) — (as Pentstemon acuminatum) Small: Bull. Torrey Bot. Club 25: 470. (1898) — (as Pentstemon)
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