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toad-flax beardtongue, toadflax penstemon

Riggin's penstemon, whorled beardtongue

Habit Subshrubs.
Stems

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

ascending to erect, 25–80 cm, retrorsely hairy, hairs pointed, not glaucous.

Leaves

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.

cauline, whorled, sometimes alternate, glabrate or retrorsely hairy, hairs pointed, not glaucous;

cauline 15–20 pairs, sessile, (5–)10–52 × 1–6(–12) mm, blade linear, sometimes lanceolate, base tapered, margins coarsely serrate-dentate, distals sometimes entire, apex acute.

Thyrses

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.

interrupted, cylindric, 4–35 cm, axis glandular-pubescent, verticillasters 5–10, cymes 1–4-flowered, 1 or 2(or 3) per node;

proximal bracts linear, rarely lanceolate, 5–34 × 1–6 mm;

peduncles and pedicels spreading to ascending, peduncles retrorsely hairy and, sometimes, glandular-pubescent distally, pedicels glandular-pubescent.

Flowers

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.

calyx lobes lanceolate, 3.5–5.8 × 1–2 mm, glandular-pubescent;

corolla bluish lavender to lavender, pinkish, pale purple, or violet, with reddish purple nectar guides, funnelform, 13–19 mm, glandular-pubescent externally, glabrous internally or sparsely white-lanate abaxially, tube 5–7 mm, throat gradually inflated, 5–6 mm diam., rounded abaxially;

stamens included, filaments glabrous or white-pubescent distally, pollen sacs parallel, 0.9–1.3 mm, distal 2/3 indehiscent, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 9–11 mm, exserted, 0.2–0.3 mm diam., distal 6–7 mm moderately to densely lanate, hairs yellow, to 2.5 mm;

style 8–10 mm.

Capsules

5–9 × 3.5–5 mm.

4.5–7 × 3–4.5 mm.

2n

= 16.

Penstemon linarioides

Penstemon triphyllus

Phenology Flowering May–Jul.
Habitat Cliffs, rocky slopes, basalt.
Elevation 300–1800 m. (1000–5900 ft.)
Distribution
from FNA
AZ; CO; NM; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; OR; WA
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Penstemon triphyllus occurs near the Snake River in northeastern Oregon (Baker and Wallowa counties), southeastern Washington (Asotin, Franklin, Garfield, Klickitat, Okanogan, and Whitman counties), and adjacent Idaho (Adams, Idaho, Lemhi, Lewis, Nez Perce, and Valley counties), extending up the Salmon River.

(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. 103. FNA vol. 17, p. 244.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera
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. 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. 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 A. Gray: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 112. (1859) — (as Pentstemon) Douglas: Edwards’s Bot. Reg. 15: plate 1245. (1829) — (as Pentstemon triphyllum)
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