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Thompson's beardtongue, Thompson's penstemon

cup-leaf beardtongue, scarlet beardtongue

Stems

prostrate or ascending, 4–15(–25) cm, retrorsely hairy, hairs appressed, white, scalelike.

ascending to erect, 50–100(–150) cm, glabrous.

Leaves

not leathery, densely retrorsely hairy, hairs appressed, white, scalelike;

cauline 1–5 pairs, petiolate, 6–25(–33) × 2–6.5 mm, blade obovate to spatulate, base tapered, apex mucronate, sometimes rounded or obtuse.

basal and cauline, glabrous;

basal and proximal cauline 40–100 × (8–)14–30 mm, blade spatulate to ovate, base tapered, apex rounded to obtuse, rarely retuse;

cauline 5–9 pairs, sessile, 12–110 × 16–70 mm, blade oblong to ovate, base clasping to connate-perfoliate, apex obtuse to acute.

Thyrses

continuous, secund, (1–)2–12 cm, axis retrorsely hairy, hairs appressed, white, scalelike, sometimes also glandular-pubescent distally, verticillasters (1–)3–12, cymes 1–3(–5)-flowered, 1 per node;

proximal bracts spatulate to oblanceolate, 5–19 × 1.5–4 mm;

peduncles and pedicels spreading to ascending, retrorsely hairy, hairs pointed, and, sometimes, sparsely glandular-pubescent.

interrupted, cylindric, 15–50 cm, axis glabrous, verticillasters 6–10(–16), cymes 1–5-flowered;

proximal bracts ovate, 9–45 × 14–40 mm;

peduncles and pedicels glabrous.

Flowers

calyx lobes lanceolate, 4–6 × 1–1.7 mm, herbaceous- or narrowly scarious-margined, sparsely glandular-pubescent and retrorsely hairy, hairs appressed, white, scalelike;

corolla blue to violet or purple, lined internally abaxially with reddish violet nectar guides, ampliate, 10–18 mm, yellow-lanate internally abaxially, tube 6–7 mm, throat gradually inflated, 4.5–6 mm diam., 2-ridged abaxially;

stamens reaching orifice or longer pair exserted, filaments glabrous, pollen sacs divergent, navicular, 0.8–1.2(–1.4) mm, sutures papillate;

staminode 8–9 mm, exserted, flattened distally, 0.2–0.3 mm diam., tip recurved, distal 6–8 mm pubescent, hairs yellow or orange, to 0.8 mm;

style 10–13 mm.

calyx lobes lanceolate, 4.5–7 × 1.8–2.9 mm, margins entire, narrowly scarious, glabrous;

corolla red, without nectar guides, tubular-funnelform, 32–36 mm, glabrous externally, glabrous internally, tube 8–11 mm, throat abruptly inflated, 9–12 mm diam., rounded abaxially;

stamens exserted, pollen sacs opposite, explanate, 1.3–1.7 mm, sutures smooth;

staminode 18–20 mm, exserted, 0.2–0.3 mm diam., tip straight to recurved, glabrous;

style 24–31 mm.

Capsules

3.5–5.5 × 3–4 mm.

9–13 × 6–10 mm.

Penstemon thompsoniae

Penstemon murrayanus

Phenology Flowering May–Aug. Flowering Mar–Jun.
Habitat Sandy to gravelly soils, sagebrush shrublands, pine-juniper woodlands, pine forests. Sandy soils, deciduous and pine woodlands, sandhill prairies.
Elevation 1500–3400 m. (4900–11200 ft.) 10–200 m. (0–700 ft.)
Distribution
from FNA
AZ; CA; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; LA; OK; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

D. D. Keck (1937) recognized two subspecies in his treatment of Penstemon thompsoniae: subsp. jaegeri, restricted to mountains of Clark County, Nevada, which he distinguished by its few, remote stems and open inflorescences, and subsp. thompsoniae in Arizona, Nevada, and Utah, which he distinguished by its tufted stems and compact inflorescences. A morphologic continuum exists between the two subspecies.

Neese described var. desperatus from Beaver and Iron counties, Utah, and eastern Nevada, distinguishing it from var. thompsoniae by its longer stems and inflorescences, and smaller leaves. She later concluded that geographic variation in Penstemon thompsoniae was not sufficiently geographically correlated to recognize infraspecific taxa (E. C. Neese 1993).

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

F. S. Crosswhite and C. D. Crosswhite (1981) hypothesized that Penstemon murrayanus was derived from P. grandiflorus, with which it shares many morphologic features. The two species have been crossed artificially, yielding hybrids that once were commercially popular (G. Viehmeyer 1958; R. Nold 1999). Molecular data support the sister relationship of P. murrayanus and P. grandiflorus (C. A. Wessinger et al. 2016).

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

Source FNA vol. 17, p. 107. FNA vol. 17, p. 121.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei
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. 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. 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. 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
Synonyms P. pumilus var. thompsoniae, P. thompsoniae var. desperatus, P. thompsoniae subsp. jaegeri
Name authority (A. Gray) Rydberg: Bull. Torrey Bot. Club 36: 690. (1909) — (as Pentstemon) Hooker: Bot. Mag. 63: plate 3472. (1836) — (as Pentstemon)
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