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desert penstemon, Mojave beardtongue

eastern white-flower beardtongue

Habit Herbs. Herbs.
Stems

ascending to erect, (30–)60–100 cm, slightly glaucous or not.

ascending to erect, 20–80 cm, retrorsely hairy and ± glandular-lanate, retrorse hairs sometimes few or distal only, not glaucous.

Leaves

basal and proximal cauline 20–165 × 12–50 mm, blade ovate to lanceolate, base tapered, margins finely to coarsely dentate, apex obtuse to acute;

cauline 4–7 pairs, sessile or proximals short-petiolate, 45–90 × 22–76 mm, blade ovate to triangular, base tapered or sessile on proximals, auriculate-clasping to connate-perfoliate on distal ones, margins finely to coarsely dentate, apex acute.

basal and cauline, not leathery, moderately to densely glandular-lanate, especially along major veins abaxially;

basal and proximal cauline 40–138 × 7–37 mm, blade spatulate to oblanceolate or elliptic, base tapered, margins entire or ± serrate to dentate, apex rounded to obtuse or acute;

cauline 4–7 pairs, sessile or proximals sometimes petiolate, (11–)20–110 × 3–30(–40) mm, blade ovate to lanceolate, base truncate to clasping, sometimes tapered, margins entire or crenate-serrate to dentate, apex acute to acuminate.

Thyrses

interrupted or continuous, secund, (6–)12–48 cm, axis glabrous, verticillasters 4–13, cymes 1–3(–6)-flowered;

proximal bracts ovate (connate-perfoliate) or lanceolate (auriculate-clasping), (9–)16–55 × 10–60 mm;

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

interrupted, conic, (3–)8–37 cm, axis moderately to densely glandular-pubescent to glandular-lanate, verticillasters 3–6(or 7), cymes 3–10(–13)-flowered, 2 per node;

proximal bracts lanceolate, 6–40 × 1–10 mm, margins entire or ± serrate;

peduncles and pedicels ascending, moderately to densely glandular-pubescent to glandular lanate.

Flowers

calyx lobes ovate, 3–5.5 × 2–3.2 mm, glabrous or glandular-pubescent;

corolla rose pink, with reddish purple nectar guides, strongly bilabiate, ventricose, (18–)25–34 mm, glandular-pubescent externally, glandular-pubescent internally, tube 6–9 mm, length 1.6–2 times calyx lobes, throat gradually inflated, ± constricted at orifice, 7–10 mm diam., rounded abaxially;

stamens: longer pair reaching orifice, filaments of shorter pair glandular-puberulent proximally, pollen sacs explanate, 1.5–2 mm, sutures smooth;

staminode 11–17 mm, included, 0.2–0.4 mm diam., tip straight to recurved, glabrous or distal 1–2 mm sparsely to moderately lanate, hairs yellow, to 1 mm;

style 20–25 mm, glabrous.

calyx lobes ovate to broadly lanceolate, 2–5 × 1.3–2 mm, glandular-pubescent;

corolla white, without nectar guides, personate, tubular, 21–28 mm, sparsely glandular-pubescent externally, moderately to densely white-villous internally abaxially, tube 6–8 mm, throat slightly inflated, 5–8 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular to subexplanate, 1–1.2 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 13–16 mm, exserted, 0.4–0.6 mm diam., tip straight, distal 10–12 mm moderately to densely pubescent, hairs yellow, to 1.6 mm;

style 16–19 mm.

Capsules

7–12 × 4–6 mm, glabrous.

5–7 × 3–5 mm, glabrous.

Penstemon pseudospectabilis

Penstemon tenuiflorus

Phenology Flowering Apr–Jun.
Habitat Dry woods, cedar glades, prairies, barrens, cliffs.
Elevation 30–80 m. (100–300 ft.)
Distribution
from FNA
AZ; CA; NM; UT; n Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; KY; MS; TN
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 2 (2 in the flora).

Two varieties, distinguished on the basis of inflorescence indument, are largely allopatric. Penstemon ×crideri A. Nelson, a putative hybrid between P. eatonii and P. pseudospectabilis, has been reported from Arizona (A. Nelson 1936).

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

Penstemon tenuiflorus is concentrated in the Interior Low Plateaus region of western Kentucky, central Tennessee, and northwestern Alabama, and in the Black Belt subsection of the Coastal Plain of central Alabama and northeastern Mississippi.

R. K. Clements et al. (1998) observed that the leaves of Penstemon tenuiflorus bear both simple and stellate hairs, reporting only simple hairs on the leaves of closely related P. hirsutus. However, stellate hairs occur in the leaf axils of plants in some populations of P. hirsutus, and they are common on the stems. Stellate hairs also occur on other diploid, tubular-flowered eastern North American species, including P. arkansanus, P. australis, P. brevisepalus, P. canescens, P. laxiflorus, P. oklahomensis, and P. pallidus. Stellate hairs have not been observed on any of the polyploid, ventricose-flowered eastern North American species.

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

Key
1. Peduncles, pedicels, and calyx lobes glandular-pubescent.
var. pseudospectabilis
1. Peduncles, pedicels, and calyx lobes glabrous.
var. connatifolius
Source FNA vol. 17, p. 253. FNA vol. 17, p. 223.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles 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. 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. 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. pseudospectabilis var. connatifolius, P. pseudospectabilis var. pseudospectabilis
Name authority M. E. Jones: Contr. W. Bot. 12: 66. (1908) — (as Pentstemon) Pennell: Addisonia 4: 79, plate 160. (1919)
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