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

Watson's beardtongue, Watson's penstemon

Habit Subshrubs. Herbs.
Stems

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

ascending to erect, 25–60 cm, glabrous or sparsely puberulent, not glaucous.

Leaves

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.

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

cauline 4–8 pairs, short-petiolate or sessile, 30–70(–80) × 8–18(–35) mm, blade oblanceolate to lanceolate, base tapered or clasping, margins entire, apex obtuse to acute.

Thyrses

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.

continuous or interrupted, cylindric, (1.5–)5–16 cm, axis ± retrorsely hairy, verticillasters 2–6(–10), cymes (2–)6–14-flowered, 2 per node;

proximal bracts lanceolate to linear, rarely ovate, 3–60 × 1–23 mm, margins entire;

peduncles and pedicels ascending to erect, ± retrorsely hairy.

Flowers

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.

calyx lobes broadly ovate, 1.8–3(–3.5) × 1.4–2 mm, apex obtuse to acute or short-cuspidate, glabrous;

corolla blue to violet or purple, with faint reddish purple nectar guides, funnelform, 12–16(–18) mm, glabrous externally, sparsely white-villous internally abaxially, tube 4–5 mm, throat gradually inflated, 3–6 mm diam., 2-ridged abaxially;

stamens included or longer pair slightly exserted, pollen sacs opposite, navicular, 0.9–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 8–9 mm, reaching orifice, 0.2–0.3 mm diam., tip slightly recurved, distal 3–4 mm moderately to densely villous, hairs golden yellow, to 1 mm;

style 9–13 mm.

Capsules

3–5 × 2.5–4 mm, glabrous.

4–7 × 3.5–5 mm, glabrous.

2n

= 16.

Penstemon deustus

Penstemon watsonii

Phenology Flowering May–Aug.
Habitat Dry, rocky slopes, sagebrush shrublands, pine-oak and pine woodlands.
Elevation 1700–3200 m. (5600–10500 ft.)
Distribution
from FNA
CA; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; ID; NV; UT; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Penstemon watsonii is known from mountain ranges throughout the Intermountain Region. Penstemon laxus, which has been included as a variety of this species, has corollas 2–3 mm in diameter and densely white-villous internally abaxially, and is known from south-central Idaho north of the Snake River. Penstemon watsonii does enter extreme south-central Idaho but is not known to occur north of the Snake River.

(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. 200. FNA vol. 17, p. 226.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon 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. 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
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. 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. 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
Name authority Douglas ex Lindley: Edwards’s Bot. Reg. 16: plate 1318. (1830) — (as Pentstemon deustum) A. Gray: in A. Gray et al., Syn. Fl. N. Amer. 2(1): 267. (1878) — (as Pentstemon watsoni)
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