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cardinal beardtongue, scarlet beardtongue

pinto beardtongue, pinto penstemon, two-color beardtongue

Habit Herbs.
Stems

ascending to erect, 32–100 cm, glabrous, slightly glaucous.

ascending to erect, 60–150 cm, glaucous.

Leaves

glabrous, not glaucous;

basal and proximal cauline 40–80(–150) × 14–40(–60) mm, blade spatulate to obovate, oblanceolate, or elliptic, base tapered, margins entire, apex rounded to obtuse;

cauline 3–7 pairs, sessile, (11–)20–135 × 9–50 mm, blade spatulate to elliptic, ovate, or subcordate, base truncate to broadly cordate-clasping, apex rounded to acute or mucronate.

basal and proximal cauline 37–110 × 10–50 mm, blade obovate, base tapered, margins coarsely serrate to coarsely dentate, apex obtuse to acute;

cauline 4–8 pairs, sessile, 40–110 × 15–55 mm, blade ovate, base connate-perfoliate, margins coarsely serrate to coarsely dentate, apex acute to acuminate.

Thyrses

secund, (3–)6–44 cm, axis glabrous, verticillasters 3–15, cymes 2–4(–8)-flowered;

proximal bracts suborbiculate, ovate, or lanceolate, (4–)16–60 × (2–)5–45 mm;

peduncles and pedicels erect, glabrous.

interrupted, secund, 16–90 cm, axis glandular-pubescent, verticillasters 9–23, cymes 1–4-flowered;

proximal bracts ovate to lanceolate, 8–25 × 3–28 mm;

peduncles and pedicels ascending to erect, glandular-pubescent.

Flowers

calyx lobes ovate, 1.6–6 × 1.4–3 mm, margins entire or erose, glabrous;

corolla red to crimson, with reddish violet nectar guides, bilaterally symmetric, weakly bilabiate, tubular, 22–30 mm, densely yellow-villous internally abaxially, tube 6–8 mm, throat 6–8 mm diam., constricted at orifice, rounded abaxially, abaxial lobes spreading to reflexed, adaxial lobes projecting to erect;

stamens included, pollen sacs divergent, 1.5–1.9 mm, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 15–17 mm, included or slightly exserted, tip straight to recurved, distal 1–3 mm sparsely lanate, hairs yellow, to 1.5 mm;

style 18–28 mm, usually exserted.

calyx lobes ovate, 4–6 × 2.2–3 mm, glandular-pubescent;

corolla pink to rose pink, purple, or light yellow, with or without reddish or reddish purple nectar guides, strongly bilabiate, ventricose, 18–27 mm, glandular-pubescent externally, glandular-pubescent internally, and sparsely white- or yellowish lanate internally abaxially, tube 7–10 mm, length 1.7–2 times calyx lobes, throat abruptly inflated, constricted at orifice, 6–9 mm diam., rounded abaxially;

stamens: longer pair reaching orifice, filaments of shorter pair glandular-puberulent proximally, pollen sacs explanate, 1.4–1.8 mm, sutures smooth;

staminode 14–16 mm, included or exserted, 0.3–0.4 mm diam., tip recurved, distal 4–5 mm lanate, hairs yellow, to 2.8 mm, proximal 3–4 mm glandular-puberulent;

style 14–16 mm, glabrous.

Capsules

10–15 × 5–9 mm.

10–13 × 5–7 mm, glabrous or sparsely glandular-pubescent distally.

Penstemon cardinalis

Penstemon bicolor

Phenology Flowering Mar–Jun.
Habitat Gravelly soils, arroyos, roadsides, talus slopes, desert scrub, juniper woodlands.
Elevation 500–1700 m. (1600–5600 ft.)
Distribution
from FNA
NM; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Penstemon cardinalis occurs as two weakly differentiated varieties in isolated ranges of the Southern Rocky Mountains.

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

Penstemon bicolor is known from the Mojave Desert in the Black Mountains of northwestern Mohave County, Arizona, the Castle, Clark, and New York mountains of eastern San Bernardino County, California, and the desert mountain ranges of southern and western Clark County, Nevada. Two subspecies differing in corolla color have been recognized, with yellow-corolla forms restricted to Clark County, Nevada. Subspecies are not recognized here, following J. D. Morefield (2006).

Habitat destruction and genetic swamping caused by hybridization between Penstemon bicolor and P. palmeri threaten many populations of P. bicolor in the vicinity of Las Vegas, Nevada (G. Glenne 2003).

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

Key
1. Calyx lobes 1.6–3.5(–4) × 1.4–2 mm; cauline leaf blades elliptic to spatulate or ovate, not leathery; proximal bracts ovate to lanceolate.
var. cardinalis
1. Calyx lobes 4–6 × 2.3–3 mm; cauline leaf blades ovate to subcordate, sometimes elliptic, leathery; proximal bracts suborbiculate to ovate.
var. regalis
Source FNA vol. 17, p. 147. FNA vol. 17, p. 247.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Elmigera Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles
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. 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
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. 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. cardinalis var. cardinalis, P. cardinalis var. regalis
Synonyms P. palmeri var. bicolor, P. bicolor subsp. roseus, P. pseudospectabilis subsp. bicolor
Name authority Wooton & Standley: Contr. U.S. Natl. Herb. 16: 171. (1913) — (as Pentstemon) (Brandegee) Clokey & D. D. Keck: Bull. S. Calif. Acad. Sci. 38: 12. (1939)
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