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Rydberg's beardtongue, Rydberg's penstemon

beautiful penstemon, Minidoka beardtongue

Habit Herbs.
Stems

decumbent, ascending, or erect, 20–70(–120) cm, glabrous or retrorsely hairy, sometimes only in lines, not glaucous.

ascending to erect, (14–)30–60(–90) cm, glabrous or retrorsely hairy, not glaucous.

Leaves

basal and cauline, not leathery, glabrous;

basal and proximal cauline (25–)35–70(–150) × (5–)10–15(–22) mm, blade oblanceolate to elliptic, base tapered, margins entire, apex obtuse to acute, rarely mucronate;

cauline 3–6 pairs, sessile or proximals short-petiolate, 25–70(–110) × 3–24 mm, blade lanceolate to elliptic or oblong, base tapered to clasping, margins entire, apex obtuse to acute.

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

basal and proximal cauline 50–130(–150) × 5–15(–25) mm, blade oblanceolate to elliptic, base tapered, margins entire, usually undulate, apex obtuse to acute;

cauline (2 or)3–5(–8) pairs, petiolate or sessile, 49–90 × 5–15 mm, blade lanceolate, base tapered, truncate, or clasping, margins undulate, apex acute to acuminate.

Thyrses

interrupted, cylindric, 3–10(–18) cm, axis retrorsely hairy or puberulent, sometimes glabrous, verticillasters (1 or)2–7, cymes (3–)5–11-flowered, 2 per node;

proximal bracts lanceolate, (4–)11–52(–70) × (1–)2–18 mm, margins entire or erose to lacerate;

peduncles and pedicels erect, glabrous, retrorsely hairy, or puberulent.

interrupted or continuous, cylindric to ± secund, (2–)9–20(–40) cm, axis glabrous, verticillasters (3–)5–9(–25), cymes 2–8(–10)-flowered, 2 per node;

proximal bracts lanceolate, 18–50(–80) × 2–20 mm;

peduncles and pedicels glabrous.

Flowers

calyx lobes oblong to ovate or obovate, 3–8 × 1.2–3.5 mm, apex acute to acuminate or short- to long-caudate, glabrous or puberulent;

corolla violet to blue or purple, without nectar guides, funnelform, 10–20 mm, glabrous externally, sparsely white- or yellowish villous internally abaxially, tube 3–4 mm, throat gradually inflated, 3–4.5 mm diam., 2-ridged abaxially;

stamens: longer pair reaching orifice or exserted, pollen sacs opposite, navicular, 0.5–1.1 mm, dehiscing completely, connective splitting, sides glabrous, sutures smooth or ± papillate;

staminode 6–7 mm, reaching orifice, 0.2–0.4 mm diam., tip straight, distal 1.5–2 mm moderately to densely pilose, hairs golden yellow, to 1 mm;

style 8–10 mm.

calyx lobes ovate, 3–5 × 1.6–2.8 mm, margins broadly scarious, apex rounded to acute or mucronate, glabrous;

corolla violet to blue or purple, without nectar guides, funnelform to weakly ventricose, 18–22 mm, glabrous externally, glabrous internally, tube 6–8 mm, throat gradually inflated, not constricted at orifice, 5–8 mm diam., slightly 2-ridged abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent to nearly opposite, navicular-sigmoid, 1.4–1.7 mm, dehiscing incompletely, proximal 1/5 indehiscent, connective not splitting, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 9–12 mm, included, 0.6–1 mm diam., tip straight to recurved, distal 4–8 mm sparsely to moderately pilose, hairs yellow, to 1 mm;

style 13–16 mm.

Capsules

4–5 × 3–4 mm, glabrous.

9–14 × 6–8 mm.

Penstemon rydbergii

Penstemon perpulcher

Phenology Flowering May–Jul.
Habitat Sagebrush shrublands.
Elevation 600–2000 m. (2000–6600 ft.)
Distribution
from FNA
AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
ID; OR
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

As treated here, Penstemon rydbergii includes three partially sympatric varieties. D. D. Keck (1945) treated the same taxa as four species and two subspecies (P. hesperius, P. oreocharis, P. rydbergii subsp. aggregatus, P. rydbergii subsp. rydbergii, and P. vaseyanus).

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

Penstemon perpulcher is common in the Snake River Plains of southern Idaho (Ada, Bannock, Boise, Canyon, Cassia, Custer, Elmore, Gooding, Minidoka, Oneida, Owyhee, Payette, and Twin Falls counties) and western Oregon (Malheur and Wallowa counties).

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

Key
1. Calyx lobe margins lacerate, rarely erose, broadly scarious, apices acuminate or short- to long-caudate; proximal bract margins erose to lacerate proximally, sometimes entire; thyrse axes retrorsely hairy or puberulent.
var. rydbergii
1. Calyx lobe margins erose, sometimes lacerate, narrowly to broadly scarious, apices acute, acuminate, or short-caudate; proximal bract margins entire; thyrse axes glabrous or retrorsely hairy.
→ 2
2. Stems ± retrorsely hairy; thyrse axes glabrous or retrorsely hairy; corollas (10–)13–20 mm; pollen sacs (0.6–)0.8–1.1 mm.
var. aggregatus
2. Stems glabrous, rarely ± retrorsely hairy; thyrse axes glabrous, rarely ± retrorsely hairy; corollas 10–14 mm; pollen sacs 0.5–0.7(–0.8) mm.
var. oreocharis
Source FNA vol. 17, p. 220. FNA vol. 17, p. 176.
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. 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. 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. 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. rydbergii var. aggregatus, P. rydbergii var. oreocharis, P. rydbergii var. rydbergii
Name authority A. Nelson: Bull. Torrey Bot. Club 25: 281. (1898) — (as Pentstemon) A. Nelson: Bot. Gaz. 52: 273. (1911) — (as Pentstemon)
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