The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

mucronate penstemon, sheep creek beardtongue

Amargosa beardtongue, Death Valley beardtongue, Death Valley penstemon

Habit Shrubs or subshrubs.
Stems

ascending to erect, 10–35(–46) cm, glabrous.

ascending to erect, 30–60 cm, glaucous.

Leaves

basal and cauline, glabrous;

basal and proximal cauline 23–65(–100) × (9–)13–40 mm, blade oblanceolate, base tapered, apex rounded to obtuse or acute;

cauline (2–)4–6(–9) pairs, sessile, (8–)20–30 × 8–26 mm, blade ovate to orbiculate, base clasping, apex mucronate.

cauline 6–12 pairs, sessile or short-petiolate, (12–)25–65 × 2–8 mm, blade lanceolate to linear, sometimes oblanceolate, base truncate or tapered, margins entire, rarely ± serrulate distally, apex obtuse to acute.

Thyrses

interrupted, cylindric, (2–)11–18(–27) cm, axis glabrous, verticillasters 6–9(–15), cymes 2–6-flowered;

proximal bracts orbiculate to ovate, 7–28 × 3–26 mm;

peduncles and pedicels glabrous.

interrupted, cylindric, 8–30 cm, axis glabrous, verticillasters 3–8, cymes 1–3-flowered;

proximal bracts lanceolate to linear, 9–28 × 2–5 mm;

peduncles and pedicels spreading to ascending, glabrous.

Flowers

calyx lobes ovate, (3–)4.5–6.5 × 1.5–2.3 mm, margins entire or erose, broadly scarious, glabrous;

corolla blue to violet, with reddish violet nectar guides, guides sometimes passing onto limb, tubular-funnelform, (10–)13–17(–20) mm, glabrous externally, sparsely white-villous internally abaxially, tube (5–)7–10 mm, throat gradually inflated, 4.5–5.5(–7) mm diam., rounded abaxially;

stamens included or longer pair reaching orifice, pollen sacs divergent to opposite, 0.7–1.1 mm, sutures papillate;

staminode 7–13 mm, reaching orifice, (0.6–)0.9–1.9 mm diam., tip strongly recurved, distal 2–5 mm moderately to densely pilose, hairs brownish yellow or golden yellow, to 1 mm;

style (7–)9–12 mm.

calyx lobes depressed-ovate to round or ovate, 3.5–6.5 × 2.5–5 mm, glabrous;

corolla bluish lavender to lavender or light pink, with reddish purple nectar guides, strongly bilabiate, ventricose-ampliate, 22–28 mm, glabrous or glandular-pubescent externally, moderately to densely white-lanate internally abaxially, sometimes also sparsely to densely glandular-pubescent internally, tube 6–8 mm, length 1–1.5 times calyx lobes, throat abruptly inflated, constricted at orifice, 8–14 mm diam., 2-ridged abaxially;

stamens included, filaments of shorter pair glandular-puberulent proximally, pollen sacs explanate to subexplanate, 1.6–2.2 mm, sutures smooth;

staminode 15–19 mm, exserted, 0.6–0.8 mm diam., tip recurved, distal 8–9 mm moderately pilose to lanate, hairs yellow, to 2.5 mm;

proximal 5–6 mm glandular-pubescent;

style 19–24 mm, glabrous.

Capsules

8–10 × 6–7 mm.

9–13 × 5–7 mm, glabrous.

2n

= 16.

= 16.

Penstemon mucronatus

Penstemon fruticiformis

Phenology Flowering May–Jun.
Habitat Sandy or gravelly soils, juniper and pinyon-juniper woodlands.
Elevation 1500–2500 m. (4900–8200 ft.)
Distribution
from FNA
CO; UT; WY
[WildflowerSearch map]
from FNA
CA; NV
[WildflowerSearch map]
[BONAP county map]
Discussion

Penstemon mucronatus is known from Moffat and Rio Blanco counties, Colorado, Daggett and Uintah counties, Utah, and Carbon and Sweetwater counties, Wyoming. E. C. Neese (1993) considered it transitional to P. pachyphyllus var. pachyphyllus in northeastern Utah and treated it as a variety of that species. The two taxa often have similar leaf morphologies; P. mucronatus usually is easily distinguished from P. pachyphyllus var. pachyphyllus by its narrower staminode bearing shorter, less tangled hairs at the apex and nectar guides that extend onto the corolla limbs. Flowers of P. mucronatus are in many respects more similar to those of P. osterhoutii than they are to those of P. pachyphyllus. A chromosome count reported for P. pachyphyllus by F. S. Crosswhite and S. Kawano (1965) is referable to P. mucronatus.

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

Varieties 2 (2 in the flora).

Penstemon fruticiformis is known from the Mojave Desert. Specimens from the Kingston Range and the eastern flank of the southern Sierra Nevada sometimes combine features of P. fruticiformis and P. incertus.

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

Key
1. Corollas glabrous externally; calyx lobes depressed-ovate to round or ovate, 3.5–5 × 3.2–5 mm.
var. fruticiformis
1. Corollas ± glandular-pubescent externally; calyx lobes ovate, 4.5–6.5 × 2.5–4 mm.
var. amargosae
Source FNA vol. 17, p. 121. FNA vol. 17, p. 250.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Coerulei Plantaginaceae > Penstemon > subg. Penstemon > sect. Spectabiles
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. 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. 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. fruticiformis var. amargosae, P. fruticiformis var. fruticiformis
Synonyms P. pachyphyllus var. mucronatus
Name authority N. H. Holmgren: Brittonia 31: 234, fig. 10. (1979) Coville: Contr. U.S. Natl. Herb. 4: 170. (1893) — (as Pentstemon)
Web links