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abajo beardtongue, handsome beardtongue, handsome penstemon

thread-leaf beardtongue

Habit Herbs or subshrubs.
Stems

ascending to erect, 14–40(–60) cm, glabrous.

ascending to erect, 16–50 cm, puberulent to retrorsely hairy, hairs pointed, not glaucous.

Leaves

basal and cauline, glabrous;

basal and proximal cauline 40–65(–110) × 8–20(–30) mm, blade obovate, base tapered, apex obtuse to acute, sometimes mucronate;

cauline 2–4 pairs, sessile, (9–)12–60 × 7–26 mm, blade lanceolate to ovate or elliptic, base tapered to clasping or cordate-clasping, apex obtuse to acute, sometimes mucronate.

cauline, opposite, puberulent, hairs pointed, or glabrous, not glaucous;

cauline 8–12 pairs, sessile, 12–70 × 0.5–1(–2) mm, blade linear, base not tapered, margins entire, apex acute.

Thyrses

interrupted or ± continuous, secund, sometimes cylindric, 5–23 cm, axis glabrous, verticillasters 4–8, cymes 1–3(or 4)-flowered;

proximal bracts ovate to lanceolate, (3–)7–38 × (1–)2–18 mm;

peduncles and pedicels glabrous, peduncles to 28 mm.

interrupted, cylindric, 9–22 cm, axis glandular-pubescent, verticillasters 1–5, cymes 1–3-flowered, (1 or)2 per node;

proximal bracts linear, 9–30 × 0.5–1 mm;

peduncles and pedicels spreading to ascending, glandular-pubescent.

Flowers

calyx lobes ovate to lanceolate, 5–6.7(–7.2) × 2–3(–3.7) mm, margins entire or erose, broadly scarious, glabrous;

corolla lavender to violet, blue, pinkish blue, or white, with or without reddish violet nectar guides, tubular-funnelform, 17–20(–22) mm, glabrous externally, sparsely white-villous internally abaxially or glabrous, tube 5–8 mm, throat gradually inflated, 5–6 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs opposite, 1.1–1.6 mm, sutures papillate;

staminode 8–9 mm, reaching orifice or slightly exserted, 0.6–1 mm diam., tip strongly recurved, distal 3–4 mm sparsely to densely villous, hairs mostly along margins, yellowish, to 1 mm;

style 10–12 mm.

calyx lobes ovate to lanceolate, 2–4.5 × 0.7–1.7 mm, glandular-pubescent;

corolla light purple to violet or purple, without nectar guides, funnelform, 13–18 mm, glandular-pubescent externally, glabrous internally, tube 3–4 mm, throat gradually inflated, 5–7 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice, filaments glabrous, pollen sacs parallel, 1.2–1.6 mm, distal 1/2 indehiscent, sides pubescent, hairs white, to 0.5 mm near filament attachment, sutures denticulate, teeth to 0.2 mm;

staminode 10–12 mm, included or reaching orifice, 0.3–0.5 mm diam., glabrous;

style 11–15 mm.

Capsules

9–12 × 5–7 mm.

5–7.5 × 2.5–4 mm.

Seeds

3.5–5 mm.

2n

= 16.

Penstemon lentus

Penstemon filiformis

Phenology Flowering Jun–Jul.
Habitat Rocky shrublands, pine woodlands.
Elevation 400–600 m. (1300–2000 ft.)
Distribution
from FNA
AZ; CO; NM; UT
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Penstemon lentus is found in the Four Corners region of the Colorado Plateau. Reported differences (N. H. Holmgren 1984) between the two varieties in the sizes of the pollen sacs appear to be inconsistent and not taxonomically useful.

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

Penstemon filiformis is known from Lake, Shasta, Siskiyou, and Trinity counties.

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

Key
1. Corollas lavender to violet, blue, or pinkish blue; Arizona, Colorado, New Mexico, Utah.
var. lentus
1. Corollas white; San Juan County, Utah.
var. albiflorus
Source FNA vol. 17, p. 120. FNA vol. 17, p. 233.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei 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. 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. 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. lentus var. albiflorus, P. lentus var. lentus
Synonyms P. laetus subsp. filiformis
Name authority Pennell: Contr. U.S. Natl. Herb. 20: 359. (1920) (D. D. Keck) D. D. Keck: in L. Abrams and R. S. Ferris, Ill. Fl. Pacific States 3: 761. (1951)
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