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mat beardtongue, mat penstemon

Shoshone beardtongue, Tiehm's beardtongue

Habit Herbs.
Stems

prostrate, only tip ascending, 2–8(–10) cm, not cinereous, retrorsely hairy, hairs pointed.

ascending to erect, 6–20 cm, retrorsely hairy, hairs appressed, white, ± scalelike, not glaucous.

Leaves

not leathery, not cinereous, retrorsely hairy, hairs pointed;

cauline 3–20 pairs, petiolate, 2.5–14(–21) × 1–4 mm, blade obovate to spatulate, oblanceolate, or linear, base tapered, apex rounded to acute or mucronate.

cauline, opposite, retrorsely hairy, hairs white, scalelike, not glaucous;

cauline 1–4 pairs, petiolate, 15–45 × 7–24 mm, blade ovate to spatulate or lanceolate, base tapered, margins entire, apex rounded to acute.

Thyrses

continuous, cylindric to secund, 0.5–3 cm, axis retrorsely hairy to retrorsely cinereous, hairs pointed, sometimes also glandular-pubescent, verticillasters 1–5, cymes 1–3-flowered, 1 per node;

proximal bracts linear, 2.8–13(–17) × 0.7–3 mm;

peduncles and pedicels ascending to erect, retrorsely hairy to retrorsely cinereous, hairs pointed, and glandular-pubescent.

interrupted, cylindric, 2–7 cm, axis glandular-pubescent, sometimes also retrorsely hairy or appressed-hairy proximally, hairs white, scalelike, verticillasters 3 or 4(–7), cymes (1 or)2–5-flowered, 1 or 2 per node;

proximal bracts lanceolate, 9–25 × 1–5 mm;

peduncles and pedicels ascending, glandular-pubescent.

Flowers

calyx lobes lanceolate to linear, 4–6.5(–8.5) × 1–1.5(–1.9) mm, herbaceous- or narrowly scarious-margined, retrorsely hairy, hairs pointed, and sparsely glandular-pubescent;

corolla blue to purplish lavender or lavender, lined internally abaxially with reddish violet nectar guides, funnelform, 10–17(–21) mm, yellow-villous internally abaxially, tube 5–6 mm, throat gradually inflated, 4.5–6 mm diam., 2-ridged abaxially;

stamens: longer pair reaching orifice or exserted, filaments glabrous, pollen sacs opposite, navicular to explanate, 0.6–1.2 mm, sutures papillate;

staminode 9–12 mm, reaching orifice, flattened distally, 0.3–0.5 mm diam., tip straight to recurved, distal 7–9 mm densely pilose, hairs golden yellow, to 1 mm;

style 13–15 mm.

calyx lobes lanceolate, 4–4.8 × 1.4–2 mm, glandular-pubescent;

corolla violet to lavender, without nectar guides, abaxial ridges usually white, weakly ventricose, 15–20 mm, glandular-pubescent externally, glabrous internally, tube 4–6 mm, throat gradually inflated, 4–5 mm diam., 2-ridged abaxially;

stamens included or longer pair reaching orifice, filaments glabrous, pollen sacs nearly parallel to divergent, 1.1–1.6 mm, distal 2/3 indehiscent, sides glabrous, sutures denticulate, teeth to 0.1 mm;

staminode 8–10 mm, exserted, 0.3–0.6 mm diam., glabrous or sparsely pilose, hairs yellow, to 0.2 mm;

style 10–13 mm.

Capsules

3.5–5 × 3–4 mm.

6–8 × 4–5 mm.

2n

= 16.

Penstemon caespitosus

Penstemon tiehmii

Phenology Flowering Jun–Aug.
Habitat Sandy-loam soils, steep volcanic talus slopes.
Elevation 2300–2900 m. (7500–9500 ft.)
Distribution
from FNA
AZ; CO; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
NV
[BONAP county map]
Discussion

Varieties 3 (3 in the flora).

The varieties of Penstemon caespitosus are weakly differentiated and largely allopatric.

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

Penstemon tiehmii is known only from Mount Lewis in the Shoshone Range in Lander County.

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

Key
1. Pollen sacs 0.9–1.2 mm; leaf blades oblanceolate; Arizona, Utah.
var. desertipicti
1. Pollen sacs 0.6–0.9 mm; leaf blades obovate, spatulate, oblanceolate, or linear; Colorado, Utah, Wyoming.
→ 2
2. Leaf blades oblanceolate to linear; pollen sacs explanate, 0.6–0.8 mm; Colorado, Utah, Wyoming.
var. caespitosus
2. Leaf blades obovate or spatulate; pollen sacs navicular to subexplanate, 0.8–0.9 mm; Colorado, Utah.
var. perbrevis
Source FNA vol. 17, p. 100. FNA vol. 17, p. 244.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi 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. 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. 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. 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. 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. caespitosus var. caespitosus, P. caespitosus var. desertipicti, P. caespitosus var. perbrevis
Name authority Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 66. (1862) — (as Pentstemon) N. H. Holmgren: Brittonia 50: 159, fig. 1F–J. (1998)
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