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Thurber's beardtongue, Thurber's penstemon

hot-rock beardtongue, hot-rock penstemon, rock penstemon, scabland penstemon

Habit Subshrubs.
Stems

20–40 cm, glabrous or glabrate.

ascending to erect, (6–)15–50 cm, retrorsely hairy, sometime glabrate, not glaucous.

Leaves

10–20 pairs, 5–32 × 0.3–2 mm, blade base tapered, margins glabrous or scabrous, apex acuminate to mucronate.

cauline, opposite, subopposite, or whorled, not leathery, glabrous or retrorsely hairy;

cauline 5–9 pairs, petiolate or sessile, (7–)10–50(–52) × (0.5–)1–20 mm, blade oblanceolate to ovate or spatulate, lanceolate to linear distally, base of proximals tapered, distals clasping, margins serrate to serrulate, rarely entire, apex rounded to obtuse, acute, or acuminate.

Thyrses

2–15(–23) cm, verticillasters (2–)5–10(–30), cymes 1- or 2-flowered;

proximal bracts linear, 3–22 × 0.2–1 mm;

peduncles and pedicels glabrous or scabrous.

interrupted, cylindric, 6–30 cm, axis ± glandular-pubescent, verticillasters 5–11, cymes 1–6-flowered, 2 per node;

proximal bracts lanceolate to linear, 6–40 × 1–4 mm, margins entire or serrate to serrulate;

peduncles and pedicels ascending to erect, glandular-pubescent.

Flowers

calyx lobes ovate, 1–2.7 × 0.9–1.5 mm;

corolla lavender to violet, lined internally abaxially with reddish purple nectar guides, funnelform, 8–14 mm, glandular-pubescent internally in 2 lines on abaxial surface, sometimes also in sinuses of adaxial lobes, tube (1.5–)2–3 mm, throat 3–5 mm diam.;

stamens included or longer pair reaching orifice or barely exserted, pollen sacs 0.4–0.5 mm;

staminode 5–6 mm;

style 7–9 mm.

calyx lobes ovate to lanceolate, 2.3–7 × 0.6–1.9 mm, glandular-pubescent;

corolla white to ochroleucous, sometimes tinged lavender, with brownish or purple nectar guides, funnelform, 9–18 mm, glabrate to glandular-pubescent externally, glandular-pubescent internally, sometimes glabrous or glabrate adaxially, tube 4–5 mm, throat slightly inflated, 2.5–5 mm diam., slightly 2-ridged abaxially;

stamens: longer pair slightly exserted, pollen sacs opposite, explanate, 0.4–0.8 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 8–9 mm, exserted, 0.2–0.3 mm diam., tip straight, glabrous or distal 0.5–2.5 mm sparsely pilose or villous, hairs yellow or white, to 0.5 mm;

style 7–10 mm.

Capsules

(4–)5–8 × 3–4 mm.

3–5 × 2.5–4 mm, glabrous.

2n

= 16.

Penstemon thurberi

Penstemon deustus

Phenology Flowering Apr–Aug(–Sep).
Habitat Sandy or rocky slopes, chaparral, creosote shrublands, pine-juniper woodlands.
Elevation 500–1200(–2100) m. (1600–3900(–6900) ft.)
Distribution
from FNA
AZ; CA; NM; NV; TX; UT; Mexico (Baja California, Chihuahua)
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Plants of Penstemon thurberi from northern Clark County, Nevada, with corollas 8–9 mm and capsules 4–5 mm have been treated as var. anestius.

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

Varieties 4 (4 in the flora).

Penstemon deustus comprises four marginally discrete varieties. Extreme forms of each variety are distinctive, but extensive zones of contact exist among the varieties, and populations frequently exhibit degrees of intermediacy, especially in Oregon where all four varieties occur.

The Paiute and Shoshoni tribes, centered in the Great Basin, used Penstemon deustus to treat dermatological, gastrointestinal, immunological, and other disorders (D. E. Moerman 1998).

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

Key
1. Leaves whorled, sometimes opposite or subopposite, blades oblanceolate or lanceolate to linear, margins serrate to serrulate distally or entire.
var. variabilis
1. Leaves opposite, blades ovate, spatulate, oblanceolate, or lanceolate, margins sharply to obscurely serrate, sometimes entire.
→ 2
2. Calyx lobes lanceolate, (3.5–)4–7 mm, apices acuminate; corollas 9–12 mm; cauline leaf blade margins sharply serrate.
var. suffrutescens
2. Calyx lobes ovate to lanceolate, 2.3–5(–6.3) mm, apices acute to acuminate; corollas 10–18 mm; cauline leaf blade margins obscurely to sharply serrate, sometimes entire.
→ 3
3. Corollas 12–18 mm, glandular-pubescent externally, glandular-pubescent internally, sometimes obscurely adaxially, abaxial lobes white to ochroleucous, sometimes tinged lavender.
var. deustus
3. Corollas 10–12(–15) mm, glabrate or glandular-pubescent externally, glabrous internally, or glabrate or glandular-pubescent abaxially and glabrous adaxially, abaxial lobes brown, sometimes white to ochroleucous.
var. pedicillatus
Source FNA vol. 17, p. 95. FNA vol. 17, p. 200.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Ambigui 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. 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. 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. 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. deustus var. deustus, P. deustus var. pedicillatus, P. deustus var. suffrutescens, P. deustus var. variabilis
Synonyms P. thurberi var. anestius
Name authority Torrey: Pacif. Railr. Rep. Parke, Bot., 15. (1856) — (as Pentstemon) Douglas ex Lindley: Edwards’s Bot. Reg. 16: plate 1318. (1830) — (as Pentstemon deustum)
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