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Thurber's beardtongue, Thurber's penstemon

Big Bend beardtongue, Havard's beardtongue

Stems

20–40 cm, glabrous or glabrate.

ascending to erect, 45–150(–200) cm, glaucous.

Leaves

10–20 pairs, 5–32 × 0.3–2 mm, blade base tapered, margins glabrous or scabrous, apex acuminate to mucronate.

glabrous, glaucous;

basal and proximal cauline 75–130 × 18–50 mm, blade ovate to elliptic, base tapered, margins entire, apex rounded to obtuse;

cauline 3–7 pairs, proximals usually short-petiolate, distal ones sessile, 24–145 × 12–70 mm, blade elliptic to ovate, base tapered to clasping, margins entire, apex obtuse to acute.

Thyrses

2–15(–23) cm, verticillasters (2–)5–10(–30), cymes 1- or 2-flowered;

proximal bracts linear, 3–22 × 0.2–1 mm;

peduncles and pedicels glabrous or scabrous.

interrupted, cylindric, 14–60(–80) cm, axis glabrous, verticillasters 7–20, cymes 2–8(–18)-flowered;

proximal bracts ovate to lanceolate, 15–33 × 4–20 mm;

peduncles and pedicels ascending to erect, glabrous or sparsely glandular-pubescent.

Flowers

calyx lobes ovate, 1–2.7 × 0.9–1.5 mm;

corolla lavender to violet, lined internally abaxially with reddish purple nectar guides, funnelform, 8–14 mm, glandular-pubescent internally in 2 lines on abaxial surface, sometimes also in sinuses of adaxial lobes, tube (1.5–)2–3 mm, throat 3–5 mm diam.;

stamens included or longer pair reaching orifice or barely exserted, pollen sacs 0.4–0.5 mm;

staminode 5–6 mm;

style 7–9 mm.

calyx lobes elliptic to ovate, 3.5–5(–5.8) × 1.8–2.4 mm, margins entire or erose, sparsely glandular-pubescent;

corolla scarlet to orange, without nectar guides, bilaterally symmetric, bilabiate, tubular-funnelform, 20–28 mm, sparsely glandular-pubescent externally, glandular-pubescent internally, tube 4–7 mm, throat gradually inflated, 5–6 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs explanate, 1–1.2 mm, sutures smooth;

staminode 14–20 mm, flattened distally, 0.3–0.6 mm diam., tip straight, glabrous;

style 16–20 mm.

Capsules

(4–)5–8 × 3–4 mm.

7–12 × 5–8 mm.

2n

= 16.

Penstemon thurberi

Penstemon havardii

Phenology Flowering Apr–Aug(–Sep). Flowering Apr–Oct.
Habitat Sandy or rocky slopes, chaparral, creosote shrublands, pine-juniper woodlands. Dry, rocky slopes, streambeds.
Elevation 500–1200(–2100) m. (1600–3900(–6900) ft.) 1500–1800 m. (4900–5900 ft.)
Distribution
from FNA
AZ; CA; NM; NV; TX; UT; Mexico (Baja California, Chihuahua)
[WildflowerSearch map]
[BONAP county map]
from FNA
TX; Mexico (Chihuahua, Coahuila, Nuevo León, Zacatecas)
[BONAP county map]
Discussion

Plants of Penstemon thurberi from northern Clark County, Nevada, with corollas 8–9 mm and capsules 4–5 mm have been treated as var. anestius.

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

In Texas, Penstemon havardii is known from Brewster, Jeff Davis, and Presidio counties. Fruiting cymes of P. havardii sometimes elongate to 10 cm.

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

Source FNA vol. 17, p. 95. FNA vol. 17, p. 153.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Ambigui Plantaginaceae > Penstemon > subg. Penstemon > sect. Gentianoides
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. 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. 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. 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
Synonyms P. thurberi var. anestius
Name authority Torrey: Pacif. Railr. Rep. Parke, Bot., 15. (1856) — (as Pentstemon) A. Gray: Proc. Amer. Acad. Arts 20: 306. (1885) — (as Pentstemon havardi)
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