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Thompson's beardtongue, Thompson's penstemon

Cusick's beardtongue, Cusick's penstemon

Habit Herbs or subshrubs.
Stems

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

ascending to erect, 15–45 cm, retrorsely hairy, hairs pointed, not glaucous.

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.

cauline, opposite or subalternate, retrorsely hairy, hairs pointed, not glaucous;

cauline 4–8 pairs, short-petiolate or sessile, 16–70 × 1–8(–14) mm, blade lanceolate to linear, base tapered, margins entire, 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, 4–15 cm, axis puberulent or retrorsely hairy, verticillasters 3–10, cymes 1–5(–7)-flowered, 2 per node;

proximal bracts lanceolate to linear, 7–50 × 1–6 mm;

peduncles and pedicels ascending to erect, puberulent or retrorsely hairy.

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 ovate, 3–5.5 × 1.4–2.3 mm, glabrous or sparsely puberulent;

corolla blue to violet or purple, without nectar guides, ampliate, 16–21 mm, glabrous externally, glabrous internally, tube 4–5 mm, throat gradually inflated, 5–6 mm diam., slightly 2-ridged abaxially;

stamens included, filaments glabrous, pollen sacs parallel, 1–1.5(–1.8) mm, distal 1/2–2/3 indehiscent, sides hispidulous, hairs white, to 0.1 mm near filament attachment, sutures denticulate, teeth to 0.1 mm;

staminode 10–12 mm, reaching orifice or barely exserted, 0.5–0.7 mm diam., glabrous;

style 11–13 mm.

Capsules

3.5–5.5 × 3–4 mm.

6–7 × 4.5–6 mm.

2n

= 16.

Penstemon thompsoniae

Penstemon cusickii

Phenology Flowering May–Aug. Flowering May–Jul.
Habitat Sandy to gravelly soils, sagebrush shrublands, pine-juniper woodlands, pine forests. Rocky, often basaltic, sagebrush shrublands.
Elevation 1500–3400 m. (4900–11200 ft.) 600–1500 m. (2000–4900 ft.)
Distribution
from FNA
AZ; CA; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; OR
[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.)

Penstemon cusickii is known from west-central and southwestern Idaho (Ada, Blaine, Canyon, Elmore, Gem, Owyhee, and Washington counties) and eastern Oregon (Baker, Grant, Harney, Malheur, Union, and Wheeler counties).

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

Source FNA vol. 17, p. 107. FNA vol. 17, p. 232.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera
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. 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
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) A. Gray: Proc. Amer. Acad. Arts 16: 106. (1880) — (as Pentstemon)
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