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blue penstemon, dark blue beardtongue

Wilcox's beardtongue, Wilcox's penstemon

Habit Herbs.
Stems

ascending to erect, (17–)30–80 cm, glabrous, not or ± glaucous.

ascending to erect, (20–)35–100 cm, glabrous or sparsely to densely puberulent, sometimes also sparsely glandular-pubescent, especially distally, not glaucous.

Leaves

basal and cauline, ± leathery or not, glabrous, ± glaucous;

basal and proximal cauline 50–170 × 8–25(–35) mm, blade oblanceolate to elliptic, base tapered, margins entire, apex obtuse to acute;

cauline 3–7 pairs, sessile or proximals short-petiolate, (15–)30–90(–120) × (4–)8–25 mm, blade lanceolate to ovate, base cordate-clasping or proximals tapered, apex acute.

basal and cauline, ± leathery or not, glabrous or puberulent to pubescent, especially along midveins;

basal and proximal cauline (25–)35–190 × (5–)12–55 mm, blade triangular to ovate or lanceolate, base tapered, rarely truncate, margins ± serrate or dentate, apex acute, rarely obtuse;

cauline 2–5 pairs, short-petiolate or sessile, 35–90 × (8–)15–50 mm, blade ovate to oblong or lanceolate, base tapered to clasping or cordate-clasping, margins serrate to dentate, apex obtuse to acute.

Thyrses

continuous or interrupted, secund, (3–)7–27 cm, axis glabrous, verticillasters (3–)5–14, cymes (2 or)3–6-flowered, 2 per node;

proximal bracts lanceolate, 15–65 × 2–26 mm;

peduncles and pedicels glabrous, peduncles to 18 mm, pedicels 3–18 mm.

interrupted, cylindric to conic, (5–)8–30 cm, axis sparsely to moderately glandular-pubescent, verticillasters 3–7, cymes 3–11-flowered, 2 per node;

proximal bracts ovate to lanceolate, (8–)18–75 × (5–)8–35 mm, margins ± serrate to dentate;

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

Flowers

calyx lobes obovate to ovate, 2.5–4.5 × 2–3.4(–3.8) mm, apex mucronate, sometimes acute to acuminate, glabrous;

corolla blue to violet or purple, without nectar guides, ventricose, 24–30(–34) mm, glabrous externally, glabrous internally, tube 7–10 mm, throat gradually inflated, not constricted at orifice, 8–11 mm diam., slightly 2-ridged abaxially;

stamens: longer pair reaching orifice, pollen sacs divergent, sigmoid, 1.8–2.7(–3) mm, dehiscing incompletely, proximal 1/5 indehiscent, connective not splitting, sides hispid to hispidulous, hairs white or tan, to 0.2 mm, sutures denticulate, teeth to 0.1 mm;

staminode 14–17 mm, included, 0.5–0.7 mm diam., tip straight, distal 4–7 mm sparsely pilose, hairs yellow, to 1 mm;

style 17–23 mm.

calyx lobes ovate, 2.4–5.5 × 0.9–1.8 mm, margins broadly scarious, glandular-pubescent;

corolla blue to violet or light blue, with reddish purple nectar guides, funnelform, 13–23 mm, glandular-pubescent externally, sparsely white- or yellow-villous internally abaxially, tube 4–8 mm, throat gradually inflated, 4–9 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular to subexplanate, 0.8–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or ± papillate;

staminode 8–11 mm, reaching orifice, 0.2–0.3 mm diam., tip straight to recurved, distal 1–5 mm pilose to villous, hairs yellow, to 1.2 mm;

style 9–13 mm.

Capsules

9–13 × 5–7 mm.

4–6.5 × 3–4 mm, glabrous.

2n

= 16, 32.

Penstemon cyaneus

Penstemon wilcoxii

Phenology Flowering Jun–Aug. Flowering May–Aug.
Habitat Gravelly or sandy hillsides, sagebrush shrublands. Rocky or gravelly slopes in forests and woodlands, roadcuts.
Elevation 1400–2900 m. (4600–9500 ft.) 300–2300 m. (1000–7500 ft.)
Distribution
from FNA
ID; MT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; MT; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon cyaneus occurs from the vicinity of Yellowstone National Park westward into south-central Idaho.

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

Penstemon wilcoxii hybridizes with P. albertinus in areas of sympatry in east-central Idaho and west-central Montana (D. D. Keck 1945; A. Cronquist 1959; D. V. Clark 1971). Putative hybrids and/or introgressants exhibit varying degrees of morphologic intermediacy between the parent species. Many herbarium specimens are difficult to determine with confidence.

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

Source FNA vol. 17, p. 164. FNA vol. 17, p. 227.
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. 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. 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. wrightii, P. xylus, P. yampaënsis
Synonyms P. ovatus var. pinetorum
Name authority Pennell: Contr. U.S. Natl. Herb. 20: 351. (1920) Rydberg: Bull. Torrey Bot. Club 28: 28. (1901) — (as Pentstemon)
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