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Arizona scarlet-bugler, hackberry beardtongue

bush penstemon, gilia beardtongue, pink plains penstemon

Stems

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

(20–)30–40(–60) cm, glabrous or scabrous proximally.

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.

(7–)10–25 pairs, (3–)5–30(–40) × 0.5–1(–2.5) mm, blade base tapered, margins glabrous or scabrous, apex acuminate to mucronate.

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.

6–15 cm, verticillasters 6–10, cymes 1–3-flowered;

proximal bracts linear, 6–27(–33) × 0.3–1.5 mm;

peduncles and pedicels glabrous or scabrous.

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, 1.5–3.5 × 1–1.5 mm;

corolla pink (limb milky pink or milky white), lined internally abaxially with reddish purple nectar guides, salverform, (14–)16–22(–28) mm, glandular-pubescent internally in 2 lines on abaxial surface, tube 3–4 mm, throat 3–5 mm diam.;

stamens included, pollen sacs 0.5–0.6 mm;

staminode 7–9 mm;

style 8–10 mm.

Capsules

6–8 × 4–5 mm.

6–9 × 3–5 mm.

2n

= 16.

Penstemon subulatus

Penstemon ambiguus

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
AZ; CO; KS; NE; NM; NV; OK; TX; UT; n Mexico
[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 2 (2 in the flora).

G. T. Nisbet and R. C. Jackson (1960) reported natural hybrids between Penstemon ambiguus and P. thurberi from Lincoln and Socorro counties, New Mexico.

Some Native American tribes used Penstemon ambiguus as a drug or ceremonial plant (D. E. Moerman 1998).

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

Key
1. Stems scabrous proximally; leaf blade margins scabrous.
var. ambiguus
1. Stems glabrous; leaf blade margins glabrous or scabrous.
var. laevissimus
Source FNA vol. 17, p. 154. FNA vol. 17, p. 95.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Gentianoides Plantaginaceae > Penstemon > subg. Penstemon > sect. Ambigui
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. 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. watsonii, P. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Subordinate taxa
P. ambiguus var. ambiguus, P. ambiguus var. laevissimus
Name authority M. E. Jones: Contr. W. Bot. 12: 63. (1908) — (as Pentstemon) Torrey: Ann. Lyceum Nat. Hist. New York 2: 228. (1827) — (as Pentstemon ambiguum)
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