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Eustis Lake beardtongue, southern beardtongue

dark beardtongue, Whipple's beardtongue, Whipple's penstemon

Habit Herbs. Herbs.
Stems

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

ascending to erect, (8–)20–65(–100) cm, glabrous or ± puberulent proximally, ± puberulent or glandular-pubescent distally, 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;

basal and proximal cauline 40–90(–130) × (5–)10–30(–75) mm, blade ovate to lanceolate or elliptic, base tapered to cuneate, margins entire or ± repand, denticulate, or dentate, apex obtuse to acute;

cauline 2–5 pairs, short-petiolate or sessile, 25–60(–85) × 3–15(–25) mm, blade lanceolate to oblanceolate, base tapered to clasping or cordate-clasping, margins entire, sometimes ± repand to denticulate, apex obtuse to acute.

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 or continuous, secund, (2–)5–35 cm, axis sparsely to densely glandular-pubescent, verticillasters 2–5(–7), cymes 2–4-flowered, 2 per node;

proximal bracts lanceolate, 11–85 × 1–18 mm, margins entire or ± repand proximally;

peduncles and pedicels ascending to erect, glandular-pubescent.

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 lanceolate, 7–10 × 1–2.2 mm, glandular-pubescent;

corolla brownish purple to bluish violet, sometimes ochroleucous, lavender, or white, with alternating white or lavender and purple nectar guides in dark-colored forms, with lavender nectar guides in light-colored forms, ventricose to ventricose-ampliate, 20–27(–30) mm, glandular-pubescent externally, sparsely white-villous internally abaxially, tube 5–8 mm, throat abruptly inflated, 8–10 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice, pollen sacs opposite, explanate, 1–1.4 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth;

staminode 12–15 mm, reaching orifice or exserted, 0.6–1.1 mm diam., tip straight to slightly recurved, distal 1–3 mm sparsely to densely villous, hairs yellow, to 1 mm;

style 12–16 mm.

Capsules

6–9 × 4.5–6 mm, glabrous.

6–9 × 4–5 mm, glandular-puberulent distally.

2n

= 16.

Penstemon australis

Penstemon whippleanus

Phenology Flowering Mar–Jun. Flowering Jun–Aug(–Sep).
Habitat Sandy pine and oak woodlands, pine savannas, hammocks, granite hills, sandy open areas. Rocky slopes in subalpine forests, alpine meadows.
Elevation 10–200 m. (0–700 ft.) 2100–3700 m. (6900–12100 ft.)
Distribution
from FNA
AL; FL; GA; MS; NC; SC; TN; VA
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CO; ID; MT; NM; UT; WY
[WildflowerSearch map]
[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 whippleanus is known from forests and meadows of the Southern and Central Rocky mountains and westward into the Wasatch Mountains and Utah Plateaus. Plants with light-colored corollas often are found growing next to plants with dark-colored corollas.

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

Source FNA vol. 17, p. 195. FNA vol. 17, p. 227.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon 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. 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. 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. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Name authority Small: Fl. S.E. U.S., 1060, 1337. (1903) — (as Pentstemon) A. Gray: Proc. Amer. Acad. Arts 6: 73. (1862) — (as Pentstemon)
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