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cup-leaf beardtongue, scarlet beardtongue

toad-flax beardtongue, toadflax penstemon

Stems

ascending to erect, 50–100(–150) cm, glabrous.

ascending to erect, 8–50 cm, retrorsely hairy, hairs pointed or white, scalelike.

Leaves

basal and cauline, glabrous;

basal and proximal cauline 40–100 × (8–)14–30 mm, blade spatulate to ovate, base tapered, apex rounded to obtuse, rarely retuse;

cauline 5–9 pairs, sessile, 12–110 × 16–70 mm, blade oblong to ovate, base clasping to connate-perfoliate, apex obtuse to acute.

not leathery, glabrous, glabrate, or sparsely to densely retrorsely hairy, hairs pointed, sometimes appressed, white, scalelike;

cauline 6–12(–20) pairs, petiolate or sessile, 4–26 × 0.5–3.5 mm, blade oblanceolate to lanceolate or linear, base tapered to truncate, apex mucronate.

Thyrses

interrupted, cylindric, 15–50 cm, axis glabrous, verticillasters 6–10(–16), cymes 1–5-flowered;

proximal bracts ovate, 9–45 × 14–40 mm;

peduncles and pedicels glabrous.

continuous or interrupted, ± secund, 3–17 cm, axis glandular-pubescent, verticillasters 3–9(–12), cymes 1 or 2(or 3)-flowered, 1(or 2) per node;

proximal bracts lanceolate to linear, 6–25 × 0.7–1 mm;

peduncles and pedicels ascending to erect, retrorsely hairy, hairs pointed, and sparsely glandular-pubescent.

Flowers

calyx lobes lanceolate, 4.5–7 × 1.8–2.9 mm, margins entire, narrowly scarious, glabrous;

corolla red, without nectar guides, tubular-funnelform, 32–36 mm, glabrous externally, glabrous internally, tube 8–11 mm, throat abruptly inflated, 9–12 mm diam., rounded abaxially;

stamens exserted, pollen sacs opposite, explanate, 1.3–1.7 mm, sutures smooth;

staminode 18–20 mm, exserted, 0.2–0.3 mm diam., tip straight to recurved, glabrous;

style 24–31 mm.

calyx lobes ovate, rarely lanceolate, 4–7(–9) × 2–3 mm, broadly scarious-margined, apex acute to acuminate, glandular-pubescent, hairs pointed;

corolla blue or lavender, lined internally abaxially with reddish purple nectar guides, ventricose-ampliate, 16–20 mm, moderately white- or yellowish villous internally abaxially, tube 5–6 mm, throat abruptly inflated, 5.5–8 mm diam., slightly 2-ridged abaxially;

stamens: longer pair reaching orifice or slightly exserted, filaments glabrous, pollen sacs opposite, navicular, 0.9–1.3 mm, sutures papillate;

staminode 6–8 mm, exserted, flattened distally, 0.3–0.5 mm diam., tip straight to recurved, distal 1–5 mm densely pilose, hairs yellow or golden yellow, to 1.2 mm, rest of distal 1–7 mm glabrous or sparsely to moderately pilose;

style 10–11 mm.

Capsules

9–13 × 6–10 mm.

5–9 × 3.5–5 mm.

Penstemon murrayanus

Penstemon linarioides

Phenology Flowering Mar–Jun.
Habitat Sandy soils, deciduous and pine woodlands, sandhill prairies.
Elevation 10–200 m. (0–700 ft.)
Distribution
from FNA
AR; LA; OK; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NM; NV; UT
[WildflowerSearch map]
[BONAP county map]
Discussion

F. S. Crosswhite and C. D. Crosswhite (1981) hypothesized that Penstemon murrayanus was derived from P. grandiflorus, with which it shares many morphologic features. The two species have been crossed artificially, yielding hybrids that once were commercially popular (G. Viehmeyer 1958; R. Nold 1999). Molecular data support the sister relationship of P. murrayanus and P. grandiflorus (C. A. Wessinger et al. 2016).

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

Varieties 4 (4 in the flora).

Penstemon linarioides is widespread and highly variable. D. D. Keck (1937) recognized seven subspecies on the basis of habit, pubescence, leaf shape, and staminode bearding. Some of the variation on which those subspecies are based appears to be clinal or too variable within or among regional populations to be of taxonomic value.

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

Key
1. Leaves glabrous, glabrate, retrorsely hairy, or pubescent, hairs pointed.
var. sileri
1. Leaves sparsely to densely retrorsely hairy, hairs appressed, white, scalelike.
→ 2
2. Cauline leaf blades oblanceolate, distals sometimes lanceolate, 1.5–3.5 mm wide.
var. maguirei
2. Cauline leaf blades oblanceolate to linear, 0.5–2 mm wide.
→ 3
3. Staminodes: distal 3–5 mm densely pilose, hairs golden yellow or yellow, to 1 mm, rest of distal 1–4 mm sparsely to moderately pilose.
var. linarioides
3. Staminodes: distal 1 mm densely pilose, hairs yellow, to 0.8 mm, rest of distal 3–4 mm glabrous or sparsely pilose (with much shorter hairs).
var. coloradoensis
Source FNA vol. 17, p. 121. FNA vol. 17, p. 103.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei 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. 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. 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. 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. linarioides var. coloradoensis, P. linarioides var. linarioides, P. linarioides var. maguirei, P. linarioides var. sileri
Name authority Hooker: Bot. Mag. 63: plate 3472. (1836) — (as Pentstemon) A. Gray: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 112. (1859) — (as Pentstemon)
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