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

Arkansas beardtongue

Habit Subshrubs. Herbs.
Stems

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

ascending to erect, (18–)25–45(–61) cm, retrorsely hairy, sometimes also ± glandular-pubescent distally, 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.

basal and cauline, basal often withering by anthesis, not leathery, glabrous or sparsely retrorsely hairy, especially along midvein and margins, abaxially, glabrous or sparsely puberulent adaxially;

basal and proximal cauline 20–95 × 5–28 mm, blade spatulate or obovate to ovate, base tapered, margins subentire to ± serrate or dentate, apex rounded to obtuse or acute;

cauline (6–)8–12 pairs, short-petiolate or sessile, 22–80 × 4–20 mm, blade lanceolate, base tapered to clasping, margins ± serrate or dentate, apex acute to acuminate.

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.

interrupted, conic, 6–24 cm, axis retrorsely hairy and ± glandular-pubescent, verticillasters 4–8, cymes 3–13-flowered, 2 per node;

proximal bracts lanceolate, 6–40 × 2–12 mm, margins entire or ± dentate;

peduncles and pedicels ascending, retrorsely hairy and ± glandular-pubescent.

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 ovate, 2.8–4.5 × 1.1–2 mm, sparsely glandular-pubescent;

corolla white, with reddish purple nectar guides, tubular to tubular-funnelform, 15–19 mm, glandular-pubescent externally, moderately whitish lanate internally abaxially, tube 4–6 mm, throat slightly inflated, 4–7 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 0.8–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, exserted, 0.2–0.4 mm diam., tip straight to slightly recurved, distal 5–7 mm ± villous, hairs yellow or golden yellow, to 1.2 mm;

style 9–11 mm.

Capsules

3–5 × 2.5–4 mm, glabrous.

4–7 × 4–5 mm, glabrous.

2n

= 16.

Penstemon deustus

Penstemon arkansanus

Phenology Flowering Apr–Jun.
Habitat Rocky oak-hickory woodlands, glades, rocky stream bottoms.
Elevation 60–300 m. (200–1000 ft.)
Distribution
from FNA
CA; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; MO; OK
[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 arkansanus is centered in the Interior Highlands. The species is most similar to P. pallidus, from which it differs by its narrower, less hairy, and more numerous cauline leaves. Some specimens from the narrow zone of sympatry in north-central Arkansas and south-central Missouri exhibit varying degrees of morphologic intermediacy. Penstemon arkansanus has been reported from Illinois (R. H. Mohlenbrock 1986) and Texas (S. D. Jones et al. 1997); those reports seem unlikely.

(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. 193.
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. 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. 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. multicaulis, P. pallidus subsp. arkansanus, P. wherryi
Name authority Douglas ex Lindley: Edwards’s Bot. Reg. 16: plate 1318. (1830) — (as Pentstemon deustum) Pennell: Proc. Acad. Nat. Sci. Philadelphia 73: 493. (1922)
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