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cardinal beardtongue, scarlet beardtongue

Watson's beardtongue, Watson's penstemon

Habit Herbs.
Stems

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

ascending to erect, 25–60 cm, glabrous or sparsely puberulent, not 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.

essentially cauline, basal absent or poorly developed, not leathery, glabrous or puberulent;

cauline 4–8 pairs, short-petiolate or sessile, 30–70(–80) × 8–18(–35) mm, blade oblanceolate to lanceolate, base tapered or clasping, margins entire, apex obtuse to acute.

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 or interrupted, cylindric, (1.5–)5–16 cm, axis ± retrorsely hairy, verticillasters 2–6(–10), cymes (2–)6–14-flowered, 2 per node;

proximal bracts lanceolate to linear, rarely ovate, 3–60 × 1–23 mm, margins entire;

peduncles and pedicels ascending to erect, ± retrorsely hairy.

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 broadly ovate, 1.8–3(–3.5) × 1.4–2 mm, apex obtuse to acute or short-cuspidate, glabrous;

corolla blue to violet or purple, with faint reddish purple nectar guides, funnelform, 12–16(–18) mm, glabrous externally, sparsely white-villous internally abaxially, tube 4–5 mm, throat gradually inflated, 3–6 mm diam., 2-ridged abaxially;

stamens included or longer pair slightly exserted, pollen sacs opposite, navicular, 0.9–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 8–9 mm, reaching orifice, 0.2–0.3 mm diam., tip slightly recurved, distal 3–4 mm moderately to densely villous, hairs golden yellow, to 1 mm;

style 9–13 mm.

Capsules

10–15 × 5–9 mm.

4–7 × 3.5–5 mm, glabrous.

2n

= 16.

Penstemon cardinalis

Penstemon watsonii

Phenology Flowering May–Aug.
Habitat Dry, rocky slopes, sagebrush shrublands, pine-oak and pine woodlands.
Elevation 1700–3200 m. (5600–10500 ft.)
Distribution
from FNA
NM; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; ID; NV; 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.)

Penstemon watsonii is known from mountain ranges throughout the Intermountain Region. Penstemon laxus, which has been included as a variety of this species, has corollas 2–3 mm in diameter and densely white-villous internally abaxially, and is known from south-central Idaho north of the Snake River. Penstemon watsonii does enter extreme south-central Idaho but is not known to occur north of the Snake River.

(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. 226.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Elmigera 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. 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. 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. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Subordinate taxa
P. cardinalis var. cardinalis, P. cardinalis var. regalis
Name authority Wooton & Standley: Contr. U.S. Natl. Herb. 16: 171. (1913) — (as Pentstemon) A. Gray: in A. Gray et al., Syn. Fl. N. Amer. 2(1): 267. (1878) — (as Pentstemon watsoni)
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