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Sonoran beardtongue

low beardtongue, lowly penstemon

Habit Herbs.
Stems

20–90 cm, retrorsely hairy, sometimes glabrescent.

decumbent to erect, (2–)5–30(–65) cm, retrorsely hairy, not glaucous.

Leaves

glabrous or retrorsely hairy;

basal and proximal cauline 16–80 × 3–10 mm, blade oblanceolate to lanceolate, base tapered, margins entire, apex obtuse to acute;

cauline 6–15(–20) pairs, 45–150 × 1–6 mm, blade linear, base tapered, apex acute to acuminate.

basal and cauline, not leathery, glabrous or retrorsely hairy;

basal and proximal cauline (8–)15–105 × 2–22(–32) mm, blade obovate to ovate or oblanceolate, base tapered, margins entire, sometimes serrulate or serrate, apex obtuse to acute;

cauline (1 or)2–4 pairs, sessile or proximals short-petiolate, 10–35(–45) × 1–11 mm, blade obovate to oblanceolate or lanceolate, base tapered to clasping, margins entire, rarely ± serrate, apex obtuse to acute.

Thyrses

cylindric to ± secund, 10–35 cm, axis glabrous, verticillasters (2–)5–8, cymes (1 or)2–4(or 5)-flowered;

proximal bracts linear, 8–30(–80) × 0.5–2 mm;

peduncles and pedicels glabrous or pedicels rarely glandular-pubescent.

interrupted, cylindric to ± secund, (1–)3–20(–39) cm, axis moderately glandular-pubescent, verticillasters (1–)3–9(–11), cymes (1 or)2–6(–11)-flowered, 2 per node;

proximal bracts lanceolate, rarely ovate, 6–34(–48) × 1–11 mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent and, usually, retrorsely hairy.

Flowers

calyx lobes elliptic to ovate, 4.2–7(–8.5) × 2–2.6(–3.5) mm, glabrous, rarely glandular-pubescent;

corolla violet to blue, lavender, or purple, lined internally abaxially with reddish purple nectar guides, ventricose, 23–37 mm, glabrous internally, tube 7–10 mm, throat abruptly inflated, 9–10 mm diam., slightly 2-ridged abaxially;

stamens included, pollen sacs parallel to divergent, 1.6–1.8 mm, sutures denticulate, teeth to 0.2 mm;

staminode 20–23 mm, exserted, 1.8–2.6 mm diam.;

style 20–24 mm.

calyx lobes ovate to lanceolate, 2.8–5(–6) × 1–1.9 mm, margins entire or erose, apex acute, glandular-pubescent;

corolla blue to purple or violet, with reddish violet nectar guides, bilabiate, not personate, tubular-funnelform, (7–)8–19 mm, glandular-pubescent externally, sparsely to moderately white- or yellow-lanate internally abaxially, tube 2–5 mm, throat slightly inflated, (3–)4.5–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 0.5–0.8 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or papillate;

staminode (3–)7–9 mm, included, 0.1–0.3 mm diam., tip slightly recurved, distal 1–4 mm sparsely to densely pilose, hairs yellow or golden yellow, to 0.7 mm (medial hairs sparser and shorter);

style 6–12 mm.

Capsules

9–15 × 6–9 mm.

4–6 × 2.5–3.5 mm, glabrous.

Penstemon stenophyllus

Penstemon humilis

Phenology Flowering Jul–Oct.
Habitat Desert grasslands, openings in pine and pine-oak woodlands.
Elevation 1200–1700 m. (3900–5600 ft.)
Distribution
from FNA
AZ; Mexico (Chihuahua, Durango, Sonora, Zacatecas)
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; CO; ID; MT; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
Discussion

In the flora area, Penstemon stenophyllus is known from the Huachuca and Patagonia mountains in Cochise and Santa Cruz counties. In Mexico, populations occur primarily along the Sierra Madre Occidental southward to central Durango at elevations to 2300 m.

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

Varieties 3 (3 in the flora).

Penstemon humilis is widespread and extremely variable throughout its range in the western United States. Except for two fairly distinct elements in Utah, most variation in the species is contained in the widespread var. humilis. D. D. Keck (1945) and N. H. Holmgren (1984) summarized the ranges and morphologic tendencies of some of the more distinctive phases.

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

Key
1. Cauline leaf blade margins ± serrate; basal leaves (4–)7–22(–32) mm wide; sw Utah.
var. obtusifolius
1. Cauline leaf blade margins entire, rarely ± serrate distally; basal leaves 2–20 mm wide; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
→ 2
2. Basal leaves puberulent or retrorsely hairy; corollas (7–)12–19 mm; California, nw Colorado, s Idaho, sw Montana, Nevada, e Oregon, Utah, Washington, w Wyoming.
var. humilis
2. Basal leaves glabrous, sometimes ± puberulent, especially along midveins and margins; corollas 10–13 mm; nc Utah.
var. brevifolius
Source FNA vol. 17, p. 109. FNA vol. 17, p. 208.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Chamaeleon Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon
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. 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. 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. humilis var. brevifolius, P. humilis var. humilis, P. humilis var. obtusifolius
Name authority A. Gray: in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 112. (1859) — (as Pentstemon) Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 69. (1862) — (as Pentstemon)
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