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mat-root beardtongue, matroot penstemon

cobaea beardtongue, cobaea penstemon

Habit Herbs.
Stems

ascending to erect, (15–)20–42 cm, retrorsely hairy or puberulent, not glaucous.

retrorsely ascending to erect, (15–)25–65(–100) cm, puberulent proximally, glandular-pubescent distally.

Leaves

essentially cauline, basal absent or poorly developed, not leathery, ± puberulent;

cauline (4 or)5–8 pairs, sessile, (20–)30–65 × (2–)4–10(–20) mm, blade ovate to lanceolate, base tapered, margins entire, apex obtuse to acute.

basal and cauline, sometimes basal absent or withering, ± leathery or not, glabrous or puberulent to pubescent;

basal and proximal cauline petiolate, 35–120(–150) × 8–55(–76) mm, blade spatulate to oblanceolate or elliptic, base tapered, margins subentire or serrate to dentate, apex rounded to acute;

cauline 4–8 pairs, sessile, 35–120(–150) × 10–45(–54) mm, blade ovate to lanceolate, base tapered to cordate-clasping, margins subentire to serrate or dentate, apex acute, rarely obtuse.

Thyrses

interrupted or continuous, cylindric, 5–14 cm, axis glandular-pubescent, verticillasters (2 or)3–6, cymes 2–4(–8)-flowered, 2 per node;

proximal bracts lanceolate to linear, 7–46 × 1–10(–20) mm, margins entire;

peduncles and pedicels ascending to erect, glandular-pubescent.

interrupted or continuous, cylindric, 10–30(–52) cm, axis densely glandular-pubescent, verticillasters 3–6(–8), cymes 2–6-flowered, 2 per node;

proximal bracts ovate, 20–78 × 8–74 mm;

peduncles and pedicels densely glandular-pubescent.

Flowers

calyx lobes lanceolate, 5–8 × 1.2–2.5 mm, glandular-pubescent;

corolla blue to dark blue, purple, or violet, with reddish purple nectar guides, bilabiate, not personate, funnelform, 16–23 mm, glandular-pubescent externally, moderately yellowish lanate internally abaxially, tube 4.5–6 mm, throat slightly inflated, 4–6 mm diam., 2-ridged abaxially;

stamens included, pollen sacs opposite, navicular to subexplanate, 0.8–1.3 mm, dehiscing completely, connective splitting, sides glabrous, sutures papillate;

staminode 10–12 mm, included, 0.3–0.4 mm diam., tip straight, distal 1 mm densely pilose or lanate, hairs yellow, to 1.4 mm, remaining distal 4–5 mm sparsely pilose, hairs yellow, to 0.5 mm;

style 11–14 mm.

calyx lobes ovate to lanceolate, (8–)10–16 × 2.5–4.5 mm, densely glandular-pubescent;

corolla white to pink or violet to purple, with reddish purple nectar guides, ventricose-ampliate, 35–55 mm, glandular-pubescent internally, tube 10–14 mm, throat abruptly inflated, slightly constricted at orifice, (15–)18–25 mm diam., rounded abaxially;

stamens included, pollen sacs opposite, explanate, 1.3–1.6 mm, dehiscing completely, sutures smooth;

staminode 23–30 mm, included or barely exserted, 0.6–0.9 mm diam., tip recurved, distal 20–25 mm sparsely to moderately villous, hairs white or golden yellow, to 3.5 mm;

style 18–34 mm.

Capsules

5–8 × 3.5–5 mm, glabrous.

13–18 × 8–10 mm.

2n

= 16.

Penstemon radicosus

Penstemon cobaea

Phenology Flowering May–Jul.
Habitat Rocky flats, slopes, ravines, sagebrush shrublands, pine woodlands.
Elevation 1500–2400 m. (4900–7900 ft.)
Distribution
from FNA
CO; ID; MT; NV; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
AR; AZ; CO; IA; IL; KS; MO; NE; NM; OH; OK; TX
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon radicosus is known from the Central Rocky Mountains and mountain ranges in the northern Great Basin. The species is most likely to be confused with P. laxus or P. watsonii.

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

Varieties 2 (2 in the flora).

Penstemon cobaea occurs widely in the central and southern Great Plains and into the Ozark Plateau. The species is a popular ornamental used in the breeding of the European or large-flowered hybrids of Penstemon (D. Lindgren and E. Wilde 2003). A chromosome count of n = 32 (R. Piotrowska 1934) appears doubtful.

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

Key
1. Corollas white to pink.
var. cobaea
1. Corollas violet to purple.
var. purpureus
Source FNA vol. 17, p. 219. FNA vol. 17, p. 131.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Penstemon Plantaginaceae > Penstemon > subg. Penstemon > sect. Cristati
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. 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. 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
Subordinate taxa
P. cobaea var. cobaea, P. cobaea var. purpureus
Name authority A. Nelson: Bull. Torrey Bot. Club 25: 280. (1898) — (as Pentstemon) Nuttall: Trans. Amer. Philos. Soc., n. s. 5: 182. (1835) — (as Pentstemon)
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