The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Harbour's beardtongue

Arkansas beardtongue

Habit Herbs. Herbs.
Caudex

rhizomelike.

Stems

decumbent, ascending, or weakly erect, 4–18 cm, retrorsely hairy, not glaucous.

ascending to erect, (18–)25–45(–61) cm, retrorsely hairy, sometimes also ± glandular-pubescent distally, not glaucous.

Leaves

cauline, not leathery, glabrate, retrorsely hairy, or puberulent;

cauline 2–4 pairs, petiolate or sessile, 7–28 × 3–12 mm, blade spatulate to oblanceolate, base tapered to clasping, margins entire, apex rounded or obtuse to acute.

basal and cauline, basal often withering by anthesis, not leathery, glabrous or sparsely retrorsely hairy, especially along midvein and margins, abaxially, glabrous or sparsely puberulent adaxially;

basal and proximal cauline 20–95 × 5–28 mm, blade spatulate or obovate to ovate, base tapered, margins subentire to ± serrate or dentate, apex rounded to obtuse or acute;

cauline (6–)8–12 pairs, short-petiolate or sessile, 22–80 × 4–20 mm, blade lanceolate, base tapered to clasping, margins ± serrate or dentate, apex acute to acuminate.

Thyrses

interrupted or continuous, ± secund, 1–3 cm, axis ± glandular-pubescent, verticillasters 1 or 2(or 3), cymes 1- or 2-flowered, 1 or 2 per node;

proximal bracts lanceolate, 17–23 × 4–10 mm, margins entire;

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

interrupted, conic, 6–24 cm, axis retrorsely hairy and ± glandular-pubescent, verticillasters 4–8, cymes 3–13-flowered, 2 per node;

proximal bracts lanceolate, 6–40 × 2–12 mm, margins entire or ± dentate;

peduncles and pedicels ascending, retrorsely hairy and ± glandular-pubescent.

Flowers

calyx lobes lanceolate, 6–10 × 1.3–2 mm, glandular-pubescent;

corolla lavender or bluish lavender to lavender-purple, without nectar guides, bilabiate, not personate, tubular-funnelform, 15–20 mm, glandular-pubescent externally, densely white-lanate internally abaxially, tube 4–6 mm, throat gradually inflated, 5–6 mm diam., prominently 2-ridged abaxially;

stamens included, pollen sacs opposite, subexplanate, 0.7–0.9 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth;

staminode 8–9 mm, included, 0.3–0.4 mm diam., tip recurved, distal 4–5 mm moderately to densely lanate, hairs yellow, to 1 mm;

style 11–12 mm.

calyx lobes ovate, 2.8–4.5 × 1.1–2 mm, sparsely glandular-pubescent;

corolla white, with reddish purple nectar guides, tubular to tubular-funnelform, 15–19 mm, glandular-pubescent externally, moderately whitish lanate internally abaxially, tube 4–6 mm, throat slightly inflated, 4–7 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular, 0.8–1 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, exserted, 0.2–0.4 mm diam., tip straight to slightly recurved, distal 5–7 mm ± villous, hairs yellow or golden yellow, to 1.2 mm;

style 9–11 mm.

Capsules

6–8 × 4–5 mm, glabrous.

4–7 × 4–5 mm, glabrous.

2n

= 16.

= 16.

Penstemon harbourii

Penstemon arkansanus

Phenology Flowering Jun–Aug. Flowering Apr–Jun.
Habitat Alpine talus, gravel slopes, boulder fields. Rocky oak-hickory woodlands, glades, rocky stream bottoms.
Elevation 3200–4200 m. (10500–13800 ft.) 60–300 m. (200–1000 ft.)
Distribution
from FNA
CO
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; MO; OK
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon harbourii is found on the high peaks of the Central Rocky Mountains. Populations have been documented in at least 17 counties. Habit, pubescence, and root characters of P. harbourii are somewhat anomalous in sect. Penstemon, prompting D. D. Keck (1945) to suggest possible ties with sect. Caespitosi or sect. Cristati. Molecular data appear to provide support for ties with sect. Caespitosi (A. D. Wolfe et al. 2006; C. A. Wessinger et al. 2016).

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

Penstemon arkansanus is centered in the Interior Highlands. The species is most similar to P. pallidus, from which it differs by its narrower, less hairy, and more numerous cauline leaves. Some specimens from the narrow zone of sympatry in north-central Arkansas and south-central Missouri exhibit varying degrees of morphologic intermediacy. Penstemon arkansanus has been reported from Illinois (R. H. Mohlenbrock 1986) and Texas (S. D. Jones et al. 1997); those reports seem unlikely.

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

Source FNA vol. 17, p. 206. FNA vol. 17, p. 193.
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. 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. 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. 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. whippleanus, P. wilcoxii, P. wrightii, P. xylus, P. yampaënsis
Synonyms P. multicaulis, P. pallidus subsp. arkansanus, P. wherryi
Name authority A. Gray: Proc. Amer. Acad. Arts 6: 71. (1862) — (as Pentstemon) Pennell: Proc. Acad. Nat. Sci. Philadelphia 73: 493. (1922)
Web links