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cardinal beardtongue, scarlet beardtongue

mat beardtongue, mat penstemon

Stems

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

prostrate, only tip ascending, 2–8(–10) cm, not cinereous, retrorsely hairy, hairs pointed.

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.

not leathery, not cinereous, retrorsely hairy, hairs pointed;

cauline 3–20 pairs, petiolate, 2.5–14(–21) × 1–4 mm, blade obovate to spatulate, oblanceolate, or linear, base tapered, apex rounded to acute or mucronate.

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.

continuous, cylindric to secund, 0.5–3 cm, axis retrorsely hairy to retrorsely cinereous, hairs pointed, sometimes also glandular-pubescent, verticillasters 1–5, cymes 1–3-flowered, 1 per node;

proximal bracts linear, 2.8–13(–17) × 0.7–3 mm;

peduncles and pedicels ascending to erect, retrorsely hairy to retrorsely cinereous, hairs pointed, and 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 lanceolate to linear, 4–6.5(–8.5) × 1–1.5(–1.9) mm, herbaceous- or narrowly scarious-margined, retrorsely hairy, hairs pointed, and sparsely glandular-pubescent;

corolla blue to purplish lavender or lavender, lined internally abaxially with reddish violet nectar guides, funnelform, 10–17(–21) mm, yellow-villous internally abaxially, tube 5–6 mm, throat gradually inflated, 4.5–6 mm diam., 2-ridged abaxially;

stamens: longer pair reaching orifice or exserted, filaments glabrous, pollen sacs opposite, navicular to explanate, 0.6–1.2 mm, sutures papillate;

staminode 9–12 mm, reaching orifice, flattened distally, 0.3–0.5 mm diam., tip straight to recurved, distal 7–9 mm densely pilose, hairs golden yellow, to 1 mm;

style 13–15 mm.

Capsules

10–15 × 5–9 mm.

3.5–5 × 3–4 mm.

Penstemon cardinalis

Penstemon caespitosus

Distribution
from FNA
NM; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; UT; WY
[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.)

Varieties 3 (3 in the flora).

The varieties of Penstemon caespitosus are weakly differentiated and largely allopatric.

(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
1. Pollen sacs 0.9–1.2 mm; leaf blades oblanceolate; Arizona, Utah.
var. desertipicti
1. Pollen sacs 0.6–0.9 mm; leaf blades obovate, spatulate, oblanceolate, or linear; Colorado, Utah, Wyoming.
→ 2
2. Leaf blades oblanceolate to linear; pollen sacs explanate, 0.6–0.8 mm; Colorado, Utah, Wyoming.
var. caespitosus
2. Leaf blades obovate or spatulate; pollen sacs navicular to subexplanate, 0.8–0.9 mm; Colorado, Utah.
var. perbrevis
Source FNA vol. 17, p. 147. FNA vol. 17, p. 100.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Elmigera Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi
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. bicolor, P. bleaklyi, P. bracteatus, P. breviculus, P. brevisepalus, P. buckleyi, P. caesius, 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
P. caespitosus var. caespitosus, P. caespitosus var. desertipicti, P. caespitosus var. perbrevis
Name authority Wooton & Standley: Contr. U.S. Natl. Herb. 16: 171. (1913) — (as Pentstemon) Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 66. (1862) — (as Pentstemon)
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