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bunchleaf penstemon, foothill beardtongue, foothill penstemon

cobaea beardtongue, cobaea penstemon

Habit Subshrubs.
Stems

ascending to erect, 30–150 cm, glabrous or retrorsely hairy, hairs pointed, rarely glaucous.

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

Leaves

essentially cauline, basal absent or essentially so, opposite, glabrous or retrorsely hairy to puberulent, hairs pointed, rarely glaucous;

cauline 5–11 pairs, petiolate or sessile, 10–100 × 0.5–12 mm, blade oblanceolate to lanceolate or linear, base tapered to clasping, margins entire, apex 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, (6–)10–32 cm, axis glabrous or retrorsely hairy, verticillasters (3–)5–14, cymes 1(–3)-flowered, (1 or)2 per node;

proximal bracts lanceolate to linear, 5–65 × 0.5–5 mm;

peduncles and pedicels ascending to erect, glabrous or retrorsely hairy.

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 obovate to oblanceolate or ovate to lanceolate, 2.6–6(–7) × 1.3–3.3 mm, glabrous or puberulent;

corolla blue to violet or purple, without nectar guides, ventricose to ventricose-ampliate, 24–38 mm, glabrous externally, glabrous internally, tube 7–10 mm, throat gradually inflated, 8–11 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice or slightly exserted, filaments glabrous, pollen sacs parallel, 2.2–3 mm, distal 1/3–1/2 indehiscent, sides pubescent to lanate, hairs white, to 0.8 mm near filament attachment, sutures denticulate, teeth to 0.2 mm;

staminode 16–19 mm, included, 0.4–0.6 mm diam., glabrous;

style 18–27 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

6–9 × 4–5 mm.

13–18 × 8–10 mm.

2n

= 16, 32.

Penstemon heterophyllus

Penstemon cobaea

Distribution
from FNA
CA
[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

Varieties 3 (3 in the flora).

Penstemon heterophyllus apparently occurs only in California (see discussion under 209c. var. purdyi). The species includes three varieties concentrated in the Coast Ranges from Humboldt County south to San Bernardino and San Diego counties.

(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. Thyrse axes glabrous; stems glabrous, rarely retrorsely hairy; calyx lobes obovate to oblanceolate, rarely lanceolate.
var. heterophyllus
1. Thyrse axes retrorsely hairy; stems retrorsely hairy; calyx lobes ovate to lanceolate.
→ 2
2. Cauline leaves 15–45 × 0.5–4 mm, axillary fascicles present, sometimes absent.
var. australis
2. Cauline leaves (25–)30–100 × 2–12 mm, axillary fascicles absent, rarely present.
var. purdyi
1. Corollas white to pink.
var. cobaea
1. Corollas violet to purple.
var. purpureus
Source FNA vol. 17, p. 235. FNA vol. 17, p. 131.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Saccanthera 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. 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. 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. heterophyllus var. australis, P. heterophyllus var. heterophyllus, P. heterophyllus var. purdyi
P. cobaea var. cobaea, P. cobaea var. purpureus
Name authority Lindley: Edwards’s Bot. Reg. 22: plate 1899. (1836) — (as Pentstemon heterophyllum) Nuttall: Trans. Amer. Philos. Soc., n. s. 5: 182. (1835) — (as Pentstemon)
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