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mat-root beardtongue, matroot penstemon

Thompson's beardtongue, Thompson's penstemon

Habit Herbs.
Stems

ascending to erect, (15–)20–42 cm, retrorsely hairy or puberulent, not glaucous.

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

Leaves

essentially cauline, basal absent or poorly developed, not leathery, ± puberulent;

cauline (4 or)5–8 pairs, sessile, (20–)30–65 × (2–)4–10(–20) mm, blade ovate to lanceolate, base tapered, margins entire, apex obtuse to acute.

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.

Thyrses

interrupted or continuous, cylindric, 5–14 cm, axis glandular-pubescent, verticillasters (2 or)3–6, cymes 2–4(–8)-flowered, 2 per node;

proximal bracts lanceolate to linear, 7–46 × 1–10(–20) mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent.

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.

Flowers

calyx lobes lanceolate, 5–8 × 1.2–2.5 mm, glandular-pubescent;

corolla blue to dark blue, purple, or violet, with reddish purple nectar guides, bilabiate, not personate, funnelform, 16–23 mm, glandular-pubescent externally, moderately yellowish lanate internally abaxially, tube 4.5–6 mm, throat slightly inflated, 4–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular to subexplanate, 0.8–1.3 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, included, 0.3–0.4 mm diam., tip straight, distal 1 mm densely pilose or lanate, hairs yellow, to 1.4 mm, remaining distal 4–5 mm sparsely pilose, hairs yellow, to 0.5 mm;

style 11–14 mm.

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.

Capsules

5–8 × 3.5–5 mm, glabrous.

3.5–5.5 × 3–4 mm.

2n

= 16.

Penstemon radicosus

Penstemon thompsoniae

Phenology Flowering May–Jul. Flowering May–Aug.
Habitat Rocky flats, slopes, ravines, sagebrush shrublands, pine woodlands. Sandy to gravelly soils, sagebrush shrublands, pine-juniper woodlands, pine forests.
Elevation 1500–2400 m. (4900–7900 ft.) 1500–3400 m. (4900–11200 ft.)
Distribution
from FNA
CO; ID; MT; NV; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; NV; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon radicosus is known from the Central Rocky Mountains and mountain ranges in the northern Great Basin. The species is most likely to be confused with P. laxus or P. watsonii.

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

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.)

Source FNA vol. 17, p. 219. FNA vol. 17, p. 107.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi
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. 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. 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. Nelson: Bull. Torrey Bot. Club 25: 280. (1898) — (as Pentstemon) (A. Gray) Rydberg: Bull. Torrey Bot. Club 36: 690. (1909) — (as Pentstemon)
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