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toad-flax beardtongue, toadflax penstemon

Mancos penstemon, stiff beardtongue, stiff penstemon

Stems

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

ascending to erect, (11–)16–55(–70) cm, glabrous, 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.

basal and cauline, ± leathery or not, glabrous, not glaucous;

basal and proximal cauline 60–90(–150) × 5–12 mm, blade oblanceolate to lanceolate, base tapered, margins entire, apex acute;

cauline 3–5 pairs, sessile, 18–80 × 3–18 mm, blade lanceolate, base tapered to truncate or clasping, 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.

continuous or interrupted, ± secund, 5–40 cm, axis glabrous, verticillasters 4–8(–12), cymes 2- or 3(–5)-flowered, 2 per node;

proximal bracts lanceolate, 12–46(–115) × 2–15 mm, apex acuminate;

peduncles and pedicels glabrous or ± glandular, peduncles to 20 mm, pedicels 2–13(–18) mm.

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 ovate to lanceolate, (4.5–)6–8(–9) × 2–3 mm, apex acuminate to caudate, glabrous or ± glandular proximally;

corolla lavender to blue, without nectar guides, ventricose, (19–)25–32 mm, glabrous externally, glabrous internally, tube 5–7 mm, throat gradually to abruptly inflated, not constricted at orifice, 7–10 mm diam., slightly 2-ridged abaxially;

stamens: longer pair slightly exserted, pollen sacs divergent, navicular-sigmoid, 1.3–2.3 mm, dehiscing incompletely, proximal 1/5–1/4 indehiscent, connective not splitting, sides sparsely to densely lanate, hairs white, to 1 mm, sutures denticulate, teeth to 0.1 mm;

staminode (8–)11–15 mm, included, 0.5–0.1(–1.2) mm diam., tip straight to recurved, distal (2–)4–5 mm sparsely to moderately villous, hairs yellow or white, to 1 mm;

style (11–)13–21 mm.

Capsules

5–9 × 3.5–5 mm.

7–11 × 4–6 mm.

Penstemon linarioides

Penstemon strictiformis

Phenology Flowering May–Jun.
Habitat Juniper and pinyon-juniper woodlands.
Elevation 1700–2400 m. (5600–7900 ft.)
Distribution
from FNA
AZ; CO; NM; NV; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; NM; UT
[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.)

Plants of Penstemon strictiformis from southwestern Colorado (Montezuma County) and northwestern New Mexico (San Juan County) closely match the type, with large corollas, broad calyx lobes, and large pollen sacs. Plants from southeastern Utah have relatively smaller corollas, narrower calyx lobes, and smaller pollen sacs.

Penstemon strictiformis often is confused with P. strictus; many specimens from southwestern Colorado are difficult to place with certainty due to morphologic intermediacy.

(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. 180.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri
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. 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
Synonyms P. strictus subsp. strictiformis
Name authority A. Gray: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 112. (1859) — (as Pentstemon) Rydberg: Bull. Torrey Bot. Club 31: 642. (1905) — (as Pentstemon)
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