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blue penstemon, dark blue beardtongue

azure penstemon, short-stalk penstemon, small azure beardtongue

Habit Herbs or subshrubs.
Stems

ascending to erect, (17–)30–80 cm, glabrous, not or ± glaucous.

ascending to erect, (10–)15–40 cm, glabrous, glaucous.

Leaves

basal and cauline, ± leathery or not, glabrous, ± glaucous;

basal and proximal cauline 50–170 × 8–25(–35) mm, blade oblanceolate to elliptic, base tapered, margins entire, apex obtuse to acute;

cauline 3–7 pairs, sessile or proximals short-petiolate, (15–)30–90(–120) × (4–)8–25 mm, blade lanceolate to ovate, base cordate-clasping or proximals tapered, apex acute.

cauline, opposite, glabrous, sometimes proximals retrorsely hairy, hairs pointed, usually glaucous;

cauline 3–8 pairs, short-petiolate or sessile, (6–)10–50 × (2–)4–9 mm, blade oblanceolate to oblong or lanceolate, base tapered to truncate or cordate, margins entire, apex obtuse to acute.

Thyrses

continuous or interrupted, secund, (3–)7–27 cm, axis glabrous, verticillasters (3–)5–14, cymes (2 or)3–6-flowered, 2 per node;

proximal bracts lanceolate, 15–65 × 2–26 mm;

peduncles and pedicels glabrous, peduncles to 18 mm, pedicels 3–18 mm.

continuous, cylindric, 4–11 cm, axis glabrous, verticillasters 4 or 5, cymes 2–4-flowered, 2 per node;

proximal bracts ovate to oblong or lanceolate, 4–34 × 2–8 mm;

peduncles and pedicels ascending to erect, glabrous.

Flowers

calyx lobes obovate to ovate, 2.5–4.5 × 2–3.4(–3.8) mm, apex mucronate, sometimes acute to acuminate, glabrous;

corolla blue to violet or purple, without nectar guides, ventricose, 24–30(–34) mm, glabrous externally, glabrous internally, tube 7–10 mm, throat gradually inflated, not constricted at orifice, 8–11 mm diam., slightly 2-ridged abaxially;

stamens: longer pair reaching orifice, pollen sacs divergent, sigmoid, 1.8–2.7(–3) mm, dehiscing incompletely, proximal 1/5 indehiscent, connective not splitting, sides hispid to hispidulous, hairs white or tan, to 0.2 mm, sutures denticulate, teeth to 0.1 mm;

staminode 14–17 mm, included, 0.5–0.7 mm diam., tip straight, distal 4–7 mm sparsely pilose, hairs yellow, to 1 mm;

style 17–23 mm.

calyx lobes obovate to ovate or lanceolate, 3–5 × 1.5–2.5 mm, glabrous;

corolla blue to violet or purple, without nectar guides, ventricose, 14–20 mm, glabrous externally, glabrous internally, tube 4–5 mm, throat gradually inflated, 5–7 mm diam., 2-ridged abaxially;

stamens included, filaments glabrous, pollen sacs parallel, 1.4–1.8 mm, distal 1/3–1/2 indehiscent, sides hispidulous, hairs white, to 0.3 mm near filament attachment, sometimes sparsely so, sutures denticulate, teeth to 0.2 mm;

staminode 10–12 mm, included, 0.4–0.6 mm diam., glabrous or distal 0.5 mm sparsely pubescent, hairs whitish, to 0.2 mm;

style 11–14 mm.

Capsules

9–13 × 5–7 mm.

5–8 × 3.5–5 mm.

2n

= 32.

Penstemon cyaneus

Penstemon parvulus

Phenology Flowering Jun–Aug. Flowering Jun–Aug.
Habitat Gravelly or sandy hillsides, sagebrush shrublands. Rocky, open foothills and montane forests.
Elevation 1400–2900 m. (4600–9500 ft.) 500–2500(–3000) m. (1600–8200(–9800) ft.)
Distribution
from FNA
ID; MT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon cyaneus occurs from the vicinity of Yellowstone National Park westward into south-central Idaho.

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

Penstemon parvulus occurs in the Klamath Ranges of northern California and southwestern Oregon and in the southern High Sierra Nevada of south-central California.

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

Source FNA vol. 17, p. 164. FNA vol. 17, p. 239.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Glabri Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera
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. 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. 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. azureus var. parvulus, P. azureus subsp. parvulus
Name authority Pennell: Contr. U.S. Natl. Herb. 20: 351. (1920) (A. Gray) Krautter: Contr. Bot. Lab. Morris Arbor. Univ. Pennsylvania 3: 193. (1908) — (as Pentstemon)
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