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cardinal beardtongue

Habit Herbs.
Stems

glabrous or retrorsely hairy, glaucous or not.

Leaves

leathery, cauline blade ovate to subcordate, sometimes elliptic.

basal and cauline, opposite, leathery or not, glabrous, puberulent, or retrorsely hairy, glaucous or not;

basal and proximal cauline petiolate;

cauline sessile or short-petiolate, blade subcordate, ovate, spatulate, oblanceolate, lanceolate, elliptic, or linear, margins entire.

Thyrses

proximal bracts suborbiculate to ovate.

interrupted, ± secund to secund, rarely cylindric, axis glabrous, sometimes retrorsely hairy, cymes 2 per node, sometimes 1 per node (P. labrosus);

peduncles and pedicels spreading to ascending or erect.

Flowers

calyx lobes 4–6 × 2.3–3 mm.

calyx lobes: margins entire or erose, broadly scarious, sometimes scarious (P. labrosus), glabrous or glandular-pubescent;

corolla red to scarlet or orange, rarely yellow, bilaterally symmetric or nearly radially symmetric (P. eatonii), weakly to strongly bilabiate, not personate, salverform, tubular-funnelform, or tubular, glabrous externally, glabrous or hairy internally abaxially, throat slightly to gradually inflated, not constricted to constricted at orifice, rounded to slightly 2-ridged abaxially;

stamens included to exserted, filaments glabrous, pollen sacs parallel, divergent, or opposite, navicular, dehiscing incompletely, proximal 1/4–1/2 indehiscent, connective not splitting, sides glabrous or hispidulous to lanate-villous;

sutures papillate or denticulate, papillae or teeth to 0.1 mm;

staminode included or slightly exserted, flattened distally, 0.3–0.9 mm diam., tip straight, rarely recurved, glabrous or distal 5–20% hairy, hairs to 1.5 mm;

style glabrous.

Capsules

glabrous.

Seeds

brown to dark brown, angled, 1.4–4.2 mm.

Penstemon cardinalis var. regalis

Penstemon sect. Elmigera

Phenology Flowering May–Jun(–Aug).
Habitat Rocky canyons, pine woodlands.
Elevation 1400–2500 m. (4600–8200 ft.)
Distribution
from FNA
NM; TX
[BONAP county map]
w United States; Mexico
Discussion

Variety regalis is known from the Guadalupe Mountains in New Mexico (Eddy County) and the Davis, Guadalupe, and Sierra Diablo mountains in western Texas (Culberson and Jeff Davis counties).

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

Species 8 (4 in the flora).

Members of sect. Elmigera all exhibit the syndrome of characteristics usually associated with hummingbird pollination. Section Elmigera is not monophyletic; species in the flora area probably are related to species in sect. Glabri (C. A. Wessinger et al. 2016). Four species usually included in sect. Elmigera, but not in the flora area, are Penstemon henricksonii Straw, P. imberbis (Kunth) Trautvetter, P. luteus G. L. Nesom, and P. wislizeni (A. Gray) Straw; all occur in Mexico.

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

Key
1. Corollas densely yellow-villous internally abaxially, throats constricted at orifices.
P. cardinalis
1. Corollas glabrous or sparsely white- or yellow-lanate internally abaxially, throats not constricted at orifices.
→ 2
2. Corollas nearly radially symmetric, weakly bilabiate, abaxial lobes projecting to barely spreading.
P. eatonii
2. Corollas bilaterally symmetric, strongly bilabiate, abaxial lobes spreading to reflexed.
→ 3
3. Corollas tubular-funnelform; basal and proximal cauline leaf blades (6–)12–30(–35) mm wide, glabrous or sparsely to densely puberulent.
P. barbatus
3. Corollas salverform; basal and proximal cauline leaf blades 3–11 mm wide, glabrous.
P. labrosus
Source FNA vol. 17, p. 148. FNA vol. 17, p. 145.
Parent taxa Plantaginaceae > Penstemon > subg. Penstemon > sect. Elmigera > Penstemon cardinalis Plantaginaceae > Penstemon > subg. Penstemon
Sibling taxa
P. cardinalis var. cardinalis
Subordinate taxa
P. barbatus, P. cardinalis, P. eatonii, P. labrosus
Synonyms P. regalis, P. cardinalis subsp. regalis Elmigera
Name authority (A. Nelson) C. C. Freeman: PhytoKeys 80: 34. (2017) (Reichenbach ex Spach) Bentham: in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 10: 329. (1846) — (as Pentstemon)
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