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Eustis Lake beardtongue, southern beardtongue

Navajo beardtongue, Navajo Mountain beardtongue

Habit Herbs.
Stems

erect, 30–86 cm, retrorsely hairy and glandular-lanate, not glaucous.

ascending to erect, 15–65 cm, glabrous, not glaucous.

Leaves

basal and cauline, not leathery, retrorsely hairy, sometimes also glandular-pubescent, rarely glabrate;

basal and proximal cauline 32–130 × 7–40 mm, blade spatulate to oblanceolate, base tapered, margins entire or ± serrate, apex rounded to obtuse;

cauline 5–8 pairs, sessile or proximals short-petiolate, 16–122 × 3–23 mm, blade lanceolate, base clasping or tapered, margins ± serrate, apex acute to acuminate.

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

basal and proximal cauline 12–80 × 4–10(–15) mm, blade spatulate to oblanceolate or lanceolate, base tapered, margins entire, apex rounded to obtuse, or acute;

cauline 3 or 4 pairs, sessile, 12–50(–75) × 1–5 mm, blade oblanceolate to linear, base tapered, apex acute to acuminate.

Thyrses

interrupted, narrowly conic, rarely conic, 7–26 cm, axis ± glandular-pubescent, verticillasters 3–6, cymes 2–6-flowered, usually only 1 branch of each cyme elongating, others nearly sessile or distinctly shorter, 2 per node;

proximal bracts lanceolate, 3–20 × 1–4 mm, margins entire;

peduncles and pedicels erect, sometimes ascending, ± glandular-pubescent.

interrupted, secund, 2–25(–47) cm, axis glabrous, verticillasters 4–14, cymes 1- or 2(or 3)-flowered, 1 or 2 per node;

proximal bracts linear, 6–15(–68) × 1–2 mm;

peduncles and pedicels glabrous.

Flowers

calyx lobes ovate to lanceolate, 4–5.2 × 1.6–2.3 mm, sparsely glandular-pubescent;

corolla white to pinkish or light lavender, with dark purple nectar guides, tubular, 20–25 mm, glandular-pubescent externally, moderately white-lanate internally abaxially, tube 4–5 mm, throat abruptly inflated, 4.5–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 1.2–1.5 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 11–14 mm, exserted, 0.4–0.7 mm diam., tip straight to slightly recurved, distal 8–10 mm densely pilose, hairs yellow, to 2 mm;

style 10–12 mm.

calyx lobes ovate, 2.6–4 × 1.5–2.2 mm, glabrous;

corolla blue to lavender, with faint reddish purple nectar guides, ventricose, 18–23(–25) mm, glabrous externally, sparsely white-villous internally abaxially, tube 7–9 mm, throat gradually to abruptly inflated, not constricted at orifice, 7–10 mm diam., slightly 2-ridged abaxially;

stamens reaching orifice or longer pair slightly exserted, pollen sacs opposite, navicular, 1.2–1.8 mm, dehiscing incompletely, proximal 1/5 sometimes indehiscent, connective not splitting, sides lanate, rarely glabrous, hairs white, to 0.9 mm, sutures denticulate, teeth to 0.1 mm;

staminode 9–11 mm, reaching orifice, 0.5–0.7 mm diam., tip straight, glabrous;

style 12–17 mm.

Capsules

6–9 × 4.5–6 mm, glabrous.

6.9–13 × 4.5–6.5 mm.

Penstemon australis

Penstemon navajoa

Phenology Flowering Mar–Jun. Flowering Jul–Aug.
Habitat Sandy pine and oak woodlands, pine savannas, hammocks, granite hills, sandy open areas. Rocky ponderosa pine, aspen, Douglas fir, and subalpine fir forests.
Elevation 10–200 m. (0–700 ft.) 2500–3200 m. (8200–10500 ft.)
Distribution
from FNA
AL; FL; GA; MS; NC; SC; TN; VA
[WildflowerSearch map]
[BONAP county map]
from FNA
UT
[BONAP county map]
Discussion

Penstemon australis is known from the southern Atlantic Coastal Plain and eastern Gulf Coastal Plain. The species is confused most often with P. laxiflorus, which occurs farther west. Penstemon australis is distinguished from P. laxiflorus most readily by the stem vestiture; P. australis usually has stems with a mix of short, eglandular hairs and much longer, glandular hairs, while P. laxiflorus has stems with only short, retrorse hairs or, if glandular hairs also are present, they are sparse and occur just below the inflorescences. Penstemon australis also tends to have narrower inflorescences due to the unequal elongation of cyme branches. Ranges of the two species overlap in southwestern Alabama, and many specimens from Baldwin, Escambia, and Mobile counties are morphologically intermediate.

Many specimens of Penstemon from the Appalachian Piedmont, especially in northeastern Alabama, northern Georgia, central North Carolina, and western South Carolina, combine morphological features of P. australis and P. canescens. These plants usually have equally developed cyme branches (as in P. canescens) but ascending or erect peduncles and pedicels (as in P. australis). Leaf shape generally is intermediate between P. australis and P. canescens. F. W. Pennell in the 1930s annotated most such specimens as P. australis. F. S. Crosswhite (1965e) also included these specimens in his concept of P. australis, assigning them subspecies status, though he never published the subspecies names that he used in his thesis and on herbarium sheets. The relationship of these plants remains unclear; they will key to P. canescens or P. laxiflorus.

A. E. Radford et al. (1968) gave a chromosome number of n = 8 for Penstemon australis; this does not appear to be supported by any other published chromosome count.

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

Penstemon navajoa is known from the Abajo Mountains, upper Dark Canyon, and Navajo Mountain in San Juan County.

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

Source FNA vol. 17, p. 195. FNA vol. 17, p. 173.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon 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. 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. 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. 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
Name authority Small: Fl. S.E. U.S., 1060, 1337. (1903) — (as Pentstemon) N. H. Holmgren: Brittonia 30: 419, fig. 3. (1978)
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