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Rydberg's beardtongue, Rydberg's penstemon

Osterhout's 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, (6–)26–77 cm, glabrous.

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, glabrous;

basal and proximal cauline 32–150 × 9–40 mm, blade oblong to ovate, base tapered, apex obtuse to acute;

cauline 4–7 pairs, sessile, (11–)18–75 × (4–)10–38 mm, blade oblong to ovate, base clasping or cordate-clasping, apex obtuse to acute.

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, cylindric, (4–)14–37 cm, axis glabrous, verticillasters (3–)6–10(–14), cymes (1 or)2–8-flowered;

proximal bracts ovate to oblong, (6–)24–43 × (3–)16–28 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, 4–6.8 × 2–3 mm, margins erose, broadly scarious, glabrous;

corolla blue to violet or lavender, with reddish violet nectar guides, guides passing onto limb, tubular-funnelform to ventricose, 15–18 mm, glabrous externally, sparsely to moderately white-villous internally abaxially, rarely glabrous, tube 6–8 mm, throat gradually inflated, 7–10 mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent to opposite, 1.1–1.3 mm, sutures papillate;

staminode 11–13 mm, reaching orifice or slightly exserted, 2–3 mm diam., tip recurved, prominently bifurcate, distal 5–7 mm densely villous, hairs yellowish or brownish yellow, to 1.5 mm;

style 10–12 mm.

Capsules

4–5 × 3–4 mm, glabrous.

11–13 × 5–7 mm.

Penstemon rydbergii

Penstemon osterhoutii

Phenology Flowering May–Jun.
Habitat Sandy or clayey soils, sagebrush and desert shrublands, pine-juniper woodlands.
Elevation 1600–2700 m. (5200–8900 ft.)
Distribution
from FNA
AZ; CA; CO; ID; MT; NM; NV; OR; UT; WA; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CO
[WildflowerSearch map]
[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.)

Populations of Penstemon osterhoutii are known from Eagle, Garfield, Grand, Pitkin, Rio Blanco, Routt, and Summit counties. The species shares some characteristics with P. pachyphyllus; it differs by larger, sky blue corollas with violet nectar guides that extend onto the corolla limbs (as in P. mucronatus) and corollas sparsely to moderately white-villous internally, rarely glabrous, on the abaxial surfaces.

(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. 122.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei
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. 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
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) Pennell: Contr. U.S. Natl. Herb. 20: 358. (1920)
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