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desert penstemon, Mojave beardtongue

Davidson's beardtongue, Davidson's penstemon

Habit Herbs. Subshrubs, cespitose.
Stems

ascending to erect, (30–)60–100 cm, slightly glaucous or not.

ascending to erect, 4–10(–17) cm, retrorsely hairy or puberulent, not glaucous.

Leaves

basal and proximal cauline 20–165 × 12–50 mm, blade ovate to lanceolate, base tapered, margins finely to coarsely dentate, apex obtuse to acute;

cauline 4–7 pairs, sessile or proximals short-petiolate, 45–90 × 22–76 mm, blade ovate to triangular, base tapered or sessile on proximals, auriculate-clasping to connate-perfoliate on distal ones, margins finely to coarsely dentate, apex acute.

persistent, 5–10 pairs, distals usually distinctly smaller than proximals, short-petiolate or sessile, (5–)10–20(–30) × 4–11 mm, blade elliptic to orbiculate, ovate, or spatulate, base tapered, margins entire or serrulate, apex rounded to obtuse or acute, glabrous or obscurely puberulent, not glaucous.

Thyrses

interrupted or continuous, secund, (6–)12–48 cm, axis glabrous, verticillasters 4–13, cymes 1–3(–6)-flowered;

proximal bracts ovate (connate-perfoliate) or lanceolate (auriculate-clasping), (9–)16–55 × 10–60 mm;

peduncles and pedicels ascending to erect, glabrous or glandular-pubescent.

continuous, ± secund, 1–6 cm, axis retrorsely hairy proximally, retrorsely hairy and glandular-pubescent distally, verticillasters (1 or)2–7, cymes 1-flowered;

proximal bracts round to ovate or lanceolate, 3–12 × 1–6 mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent, sometimes also puberulent.

Flowers

calyx lobes ovate, 3–5.5 × 2–3.2 mm, glabrous or glandular-pubescent;

corolla rose pink, with reddish purple nectar guides, strongly bilabiate, ventricose, (18–)25–34 mm, glandular-pubescent externally, glandular-pubescent internally, tube 6–9 mm, length 1.6–2 times calyx lobes, throat gradually inflated, ± constricted at orifice, 7–10 mm diam., rounded abaxially;

stamens: longer pair reaching orifice, filaments of shorter pair glandular-puberulent proximally, pollen sacs explanate, 1.5–2 mm, sutures smooth;

staminode 11–17 mm, included, 0.2–0.4 mm diam., tip straight to recurved, glabrous or distal 1–2 mm sparsely to moderately lanate, hairs yellow, to 1 mm;

style 20–25 mm, glabrous.

calyx lobes lanceolate to linear, 7–12(–14) × 2.5–4.3 mm, glandular-pubescent;

corolla lavender to bluish lavender, violet, or purple, essentially unlined internally but abaxial ridges usually lavender or white, nearly personate, funnelform, 20–45 mm, glabrous externally, sparsely to moderately white-villous internally abaxially, tube (4–)6–12 mm, throat 7–12 mm diam.;

stamens included, pollen sacs 0.9–1.6 mm;

staminode 7–14 mm, slightly flattened distally, 0.1–0.2 mm diam., tip straight, distal 4–7 mm sparsely to densely villous, hairs whitish, to 1 mm;

style 19–26 mm.

Capsules

7–12 × 4–6 mm, glabrous.

8–13 × 5–8 mm.

Penstemon pseudospectabilis

Penstemon davidsonii

Distribution
from FNA
AZ; CA; NM; UT; n Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; NV; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Two varieties, distinguished on the basis of inflorescence indument, are largely allopatric. Penstemon ×crideri A. Nelson, a putative hybrid between P. eatonii and P. pseudospectabilis, has been reported from Arizona (A. Nelson 1936).

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

Varieties 3 (3 in the flora).

Penstemon davidsonii occurs mostly at high elevations in the Cascade Range and Sierra Nevada.

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

Key
1. Peduncles, pedicels, and calyx lobes glandular-pubescent.
var. pseudospectabilis
1. Peduncles, pedicels, and calyx lobes glabrous.
var. connatifolius
1. Corollas (30–)34–45 mm; leaf blades elliptic to ovate, sometimes spatulate, margins entire.
var. praeteritus
1. Corollas 20–36 mm; leaf blades spatulate to orbiculate or elliptic, margins serrulate or entire.
→ 2
2. Leaf blade margins entire, sometimes serrulate, apices rounded to obtuse.
var. davidsonii
2. Leaf blade margins ± serrulate, apices rounded to obtuse or acute.
var. menziesii
Source FNA vol. 17, p. 253. FNA vol. 17, p. 87.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles Plantaginaceae > Penstemon > subg. Dasanthera > sect. Erianthera
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. 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. 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. pseudospectabilis var. connatifolius, P. pseudospectabilis var. pseudospectabilis
P. davidsonii var. davidsonii, P. davidsonii var. menziesii, P. davidsonii var. praeteritus
Synonyms P. menziesii subsp. davidsonii
Name authority M. E. Jones: Contr. W. Bot. 12: 66. (1908) — (as Pentstemon) Greene: Pittonia 2: 241. (1892) — (as Pentstemon)
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