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Arizona scarlet-bugler, hackberry beardtongue

low beardtongue, lowly penstemon

Habit Herbs.
Stems

ascending to erect, 20–60 cm, glaucous, sometimes not.

decumbent to erect, (2–)5–30(–65) cm, retrorsely hairy, not glaucous.

Leaves

glabrous, glaucous;

basal and proximal cauline 28–100 × 2–11 mm, blade oblanceolate to elliptic, base tapered, margins entire, apex obtuse to acute;

cauline 3–6 pairs, sessile, (11–)30–80(–120) × 2–9 mm, blade lanceolate to linear or linear-subulate, base clasping to auriculate-clasping, margins entire, apex rounded to acute.

basal and cauline, not leathery, glabrous or retrorsely hairy;

basal and proximal cauline (8–)15–105 × 2–22(–32) mm, blade obovate to ovate or oblanceolate, base tapered, margins entire, sometimes serrulate or serrate, apex obtuse to acute;

cauline (1 or)2–4 pairs, sessile or proximals short-petiolate, 10–35(–45) × 1–11 mm, blade obovate to oblanceolate or lanceolate, base tapered to clasping, margins entire, rarely ± serrate, apex obtuse to acute.

Thyrses

interrupted, cylindric, 6–26 cm, axis glabrous, verticillasters 5–9, cymes 1–4-flowered;

proximal bracts lanceolate to linear, 6–33 × 1–4 mm;

peduncles and pedicels erect, glabrous.

interrupted, cylindric to ± secund, (1–)3–20(–39) cm, axis moderately glandular-pubescent, verticillasters (1–)3–9(–11), cymes (1 or)2–6(–11)-flowered, 2 per node;

proximal bracts lanceolate, rarely ovate, 6–34(–48) × 1–11 mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent and, usually, retrorsely hairy.

Flowers

calyx lobes ovate to lanceolate, 2–4.5 × 1.4–2.1 mm, margins entire or erose, glabrous or ± glandular along margins;

corolla scarlet, without nectar guides, nearly radially symmetric, weakly bilabiate, salverform, 18–26 mm, glabrous externally, glabrous internally, tube 4–7 mm, 1.6–3 times as long as calyx lobes, throat slightly inflated, 3–5 mm diam., rounded abaxially;

stamens: longer pair reaching orifice, pollen sacs explanate, 0.7–0.9 mm, sutures smooth;

staminode 13–14 mm, essentially terete, 0.1 mm diam., tip straight, glabrous, rarely distal 1–2 mm sparsely papillate, papillae yellow, to 0.2 mm;

style 10–19 mm.

calyx lobes ovate to lanceolate, 2.8–5(–6) × 1–1.9 mm, margins entire or erose, apex acute, glandular-pubescent;

corolla blue to purple or violet, with reddish violet nectar guides, bilabiate, not personate, tubular-funnelform, (7–)8–19 mm, glandular-pubescent externally, sparsely to moderately white- or yellow-lanate internally abaxially, tube 2–5 mm, throat slightly inflated, (3–)4.5–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 0.5–0.8 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or papillate;

staminode (3–)7–9 mm, included, 0.1–0.3 mm diam., tip slightly recurved, distal 1–4 mm sparsely to densely pilose, hairs yellow or golden yellow, to 0.7 mm (medial hairs sparser and shorter);

style 6–12 mm.

Capsules

6–8 × 4–5 mm.

4–6 × 2.5–3.5 mm, glabrous.

2n

= 16.

Penstemon subulatus

Penstemon humilis

Phenology Flowering (Feb–)Mar–May.
Habitat Rocky slopes, mesas, canyons.
Elevation 500–1300 m. (1600–4300 ft.)
Distribution
from FNA
AZ
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon subulatus has been documented in Gila, Graham, Maricopa, Mohave, Pinal, and Yuma counties in central Arizona.

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

Varieties 3 (3 in the flora).

Penstemon humilis is widespread and extremely variable throughout its range in the western United States. Except for two fairly distinct elements in Utah, most variation in the species is contained in the widespread var. humilis. D. D. Keck (1945) and N. H. Holmgren (1984) summarized the ranges and morphologic tendencies of some of the more distinctive phases.

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

Key
1. Cauline leaf blade margins ± serrate; basal leaves (4–)7–22(–32) mm wide; sw Utah.
var. obtusifolius
1. Cauline leaf blade margins entire, rarely ± serrate distally; basal leaves 2–20 mm wide; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
→ 2
2. Basal leaves puberulent or retrorsely hairy; corollas (7–)12–19 mm; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
var. humilis
2. Basal leaves glabrous, sometimes ± puberulent, especially along midveins and margins; corollas 10–13 mm; nc Utah.
var. brevifolius
Source FNA vol. 17, p. 154. FNA vol. 17, p. 208.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Gentianoides 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. 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. 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. humilis var. brevifolius, P. humilis var. humilis, P. humilis var. obtusifolius
Name authority M. E. Jones: Contr. W. Bot. 12: 63. (1908) — (as Pentstemon) Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 69. (1862) — (as Pentstemon)
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