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

mat beardtongue, mat penstemon

crested beardtongue, crested-tongue beardtongue, crested-tongue penstemon, fuzzy-tongue penstemon

Stems

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

ascending to erect, (2–)6–60 cm, retrorsely hairy, sometimes also villous or glandular-villous, or glabrate.

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.

basal and cauline, not leathery, glabrous or glabrate to retrorsely hairy and, sometimes, sparsely villous abaxially, glabrous or glabrate to retrorsely hairy and, sometimes, villous or glandular-villous adaxially;

basal and proximal cauline petiolate, (14–)22–130(–180) × 3–30(–40) mm, blade spatulate to obovate, oblanceolate, elliptic, or linear, base tapered, margins entire or ± dentate to serrate, apex rounded to obtuse or acute;

cauline 2–6 pairs, sessile or proximals short-petiolate, 18–90 × 3–20(–25) mm, blade oblanceolate to oblong, lanceolate, or linear, base tapered to clasping or cordate-clasping, margins entire or ± dentate to serrate, apex obtuse 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.

continuous or interrupted, cylindric, (1–)2–20(–27) cm, axis glandular-pubescent to glandular-villous, sometimes also retrorsely hairy, verticillasters 2–7(–9), cymes (1 or)2–6-flowered, 2 per node;

proximal bracts oblanceolate to oblong or lanceolate, 12–75 × 2–23 mm;

peduncles and pedicels glandular-villous or glandular-pubescent and, sometimes, also retrorsely hairy.

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, 5.5–13 × 1.4–3 mm, glandular-pubescent to glandular-villous;

corolla lavender to violet, purple, pink, or blue, with reddish purple nectar guides, funnelform or ventricose-ampliate, 16–35(–42) mm, sparsely to densely white- or yellow-villous internally abaxially, sometimes glandular-pubescent laterally, tube 4–9 mm, throat gradually to abruptly inflated, constricted or not at orifice, 6–14 mm diam., rounded abaxially;

stamens included, pollen sacs widely divergent to opposite, navicular to subexplanate or explanate, 0.8–1.9 mm, dehiscing completely, sutures smooth or papillate;

staminode 12–18 mm, exserted or prominently exserted, 0.3–0.9 mm diam., tip recurved, distal 6–15 mm sparsely to densely lanate, hairs yellow, yellowish, or orangish, to 4 mm, and medial hairs shorter, stiffer, and retrorse;

style 9–20 mm, glabrous or proximal 1–10 mm sparsely glandular-pubescent.

Capsules

3.5–5 × 3–4 mm.

6–13 × 4–6 mm, sparsely glandular-pubescent distally.

Penstemon caespitosus

Penstemon eriantherus

Distribution
from FNA
AZ; CO; UT; WY
[WildflowerSearch map]
[BONAP county map]
from FNA
CO; ID; MT; ND; NE; OR; SD; UT; WA; WY; AB; BC
[WildflowerSearch map]
[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.)

Varieties 5 (5 in the flora).

D. D. Keck (1938) treated this complex as three species: Penstemon cleburnei, P. eriantherus (with three varieties), and P. whitedii (with three subspecies). Most authors followed A. Cronquist (1959), who employed a broader species concept; the approach by Cronquist is followed here.

(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
1. Corollas constricted at orifices; styles 9–12(–14) mm; pollen sacs 0.8–1.2 mm.
var. cleburnei
1. Corollas not constricted at orifices; styles 9–20 mm; pollen sacs 1–1.9 mm.
→ 2
2. Stems glabrate or retrorsely hairy, rarely glandular-villous, proximally, glandular-villous distally; leaves glabrous or glabrate abaxially, glabrate or villous to glandular-villous adaxially.
var. whitedii
2. Stems retrorsely hairy and, sometimes, sparsely villous, glandular-villous, or glandular-pubescent distally; leaves retrorsely hairy and, sometimes, sparsely villous or glabrous abaxially, retrorsely hairy or puberulent and, sometimes, villous or glandular-villous adaxially.
→ 3
3. Corollas funnelform; staminodes sparsely lanate distally; leaves glabrous abaxially.
var. argillosus
3. Corollas ventricose-ampliate; staminodes moderately to densely lanate distally; leaves retrorsely hairy, sparsely villous, or glabrous abaxially.
→ 4
4. Pollen sacs explanate; stems retrorsely hairy and, usually, sparsely villous or glandular-villous distally; corollas (20–)22–35(–42) mm.
var. eriantherus
4. Pollen sacs navicular to subexplanate; stems retrorsely hairy, sometimes also glandular-pubescent distally or wholly; corollas 18–25 mm.
var. redactus
Source FNA vol. 17, p. 100. FNA vol. 17, p. 133.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Caespitosi 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. 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. 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. caespitosus var. caespitosus, P. caespitosus var. desertipicti, P. caespitosus var. perbrevis
P. eriantherus var. argillosus, P. eriantherus var. cleburnei, P. eriantherus var. eriantherus, P. eriantherus var. redactus, P. eriantherus var. whitedii
Name authority Nuttall ex A. Gray: Proc. Amer. Acad. Arts 6: 66. (1862) — (as Pentstemon) Pursh: Fl. Amer. Sept. 2: 737. (1813) — (as Pentstemon erianthera)
Web links