Penstemon linarioides

A. Gray in W. H. Emory

Rep. U.S. Mex. Bound. 2(1): 112. 1859.

Common names: Toad-flax beardtongue
Endemic
Treatment appears in FNA Volume 17. Treatment on page 103. Mentioned on page 99, 104.

Stems ascending to erect, 8–50 cm, retrorsely hairy, hairs pointed or white, scalelike. Leaves not leathery, glabrous, glabrate, or sparsely to densely retrorsely hairy, hairs pointed, sometimes appressed, white, scalelike; cauline 6–12 (–20) pairs, petiolate or sessile, 4–26 × 0.5–3.5 mm, blade oblanceolate to lanceolate or linear, base tapered to truncate, apex mucronate. Thyrses continuous or interrupted, ± secund, 3–17 cm, axis glandular-pubescent, verticillasters 3–9 (–12), cymes 1 or 2 (or 3) -flowered, 1 (or 2) per node; proximal bracts lanceolate to linear, 6–25 × 0.7–1 mm; peduncles and pedicels ascending to erect, retrorsely hairy, hairs pointed, and sparsely glandular-pubescent. Flowers: calyx lobes ovate, rarely lanceolate, 4–7 (–9) × 2–3 mm, broadly scarious-margined, apex acute to acuminate, glandular-pubescent, hairs pointed; corolla blue or lavender, lined internally abaxially with reddish purple nectar guides, ventricose-ampliate, 16–20 mm, moderately white or yellowish villous internally abaxially, tube 5–6 mm, throat abruptly inflated, 5.5–8 mm diam., slightly 2-ridged abaxially; stamens: longer pair reaching orifice or slightly exserted, filaments glabrous, pollen-sacs opposite, navicular, 0.9–1.3 mm, sutures papillate; staminode 6–8 mm, exserted, flattened distally, 0.3–0.5 mm diam., tip straight to recurved, distal 1–5 mm densely pilose, hairs yellow or golden yellow, to 1.2 mm, rest of distal 1–7 mm glabrous or sparsely to moderately pilose; style 10–11 mm. Capsules 5–9 × 3.5–5 mm.

Distribution

Ariz., Colo., N.Mex., Nev., Utah

Discussion

Varieties 4 (4 in the flora).

Penstemon linarioides is widespread and highly variable. D. D. Keck (1937) recognized seven subspecies on the basis of habit, pubescence, leaf shape, and staminode bearding. Some of the variation on which those subspecies are based appears to be clinal or too variable within or among regional populations to be of taxonomic value.

Selected References

None.

Key

1 Leaves glabrous, glabrate, retrorsely hairy, or pubescent, hairs pointed. Penstemon linarioides var. sileri
1 Leaves sparsely to densely retrorsely hairy, hairs appressed, white, scalelike. > 2
2 Cauline leaf blades oblanceolate, distals sometimes lanceolate, 1.5–3.5 mm wide. Penstemon linarioides var. maguirei
2 Cauline leaf blades oblanceolate to linear, 0.5–2 mm wide. > 3
3 Staminodes: distal 3–5 mm densely pilose, hairs golden yellow or yellow, to 1 mm, rest of distal 1–4 mm sparsely to moderately pilose. Penstemon linarioides var. linarioides
3 Staminodes: distal 1 mm densely pilose, hairs yellow, to 0.8 mm, rest of distal 3–4 mm glabrous or sparsely pilose (with much shorter hairs). Penstemon linarioides var. coloradoensis

"/4+timescorollathroat" is not declared as a valid unit of measurement for this property.

... more about "Penstemon linarioides"
glandular-pubescent +
acute +  and acuminate +
Craig C. Freeman +
A. Gray in W. H. Emory +
glandular-pubescent +
alternate +, opposite +, whorled +, helical +  and subopposite +
tapered;truncate +
Penstemon +
oblanceolate;lanceolate or linear +
not +  and leathery +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
scarious-margined +
0.7 cm7 mm <br />0.007 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
lanceolate;ovate +
short-tubular +  and short-campanulate +
0.5 cm5 mm <br />0.005 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
sessile +  and petiolate +
0.4 cm4 mm <br />0.004 m <br /> (2.6 cm26 mm <br />0.026 m <br />) +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Toad-flax beardtongue +
yellowish +, white +, lavender +  and blue +
salverform +  and tubular-funnelform +
ventricose-ampliate +
1.6 cm16 mm <br />0.016 m <br /> (2 cm20 mm <br />0.02 m <br />) +
scale-like +  and not needlelike +
Ariz. +, Colo. +, N.Mex. +, Nev. +  and Utah +
drupe-like +
curved +  and straight +
1 +  and 4 +
golden yellow +, yellow +  and white +
glabrous or +  and sparsely moderately pilose +
pointed +  and scale-like +
0.1 cm1 mm <br />0.001 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
membranous +
terminal +  and axillary +
persistent +  and deciduous +
cauline +, proximal +  and basal +
glabrate or +  and sparsely densely retrorsely hairy +
not leathery +
orbiculate;linear;orbiculate;linear;truncate;oblanceolate;obovate;oblong;elliptic;round;lanceolate;ovate +
erose +  and entire +
glabrate +, hairy +  and glandular-pubescent +
toothed +  and entire +
herbaceous +  and scarious +
axile +  and parietal +
basal +, apical +  and superior +
tenuinucellate +, unitegmic +  and hemitropous +
campylotropous +, hemianatropous +  and anatropous +
ascending +  and erect +
ascending;erect +
5 +  and 4 +
navicular-sigmoid +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
lanceolate +  and linear +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Rep. U.S. Mex. Bound. +
minute +
dark-brown +  and black +
angled +  and rounded +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (?) +  and 0.8 cm8 mm <br />0.008 m <br /> (?) +
subalternate +, alternate +, whorled +  and opposite +
climbing +  and scrambling +
sprawling +, creeping +  and prostrate +
ascending;erect +
8 cm80 mm <br />0.08 m <br /> (50 cm500 mm <br />0.5 m <br />) +
1 cm10 mm <br />0.01 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
papillate +
denticulate +
Penstemon linarioides +
Penstemon sect. Caespitosi +
species +
0.55 cm5.5 mm <br />0.0055 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
2-ridged +  and inflated +
not constricted +
secund +, interrupted +  and continuous +
cylindric +
3 cm30 mm <br />0.03 m <br /> (17 cm170 mm <br />0.17 m <br />) +
straight +
0.1 cm1 mm <br />0.001 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
gibbous +  and not spurred +
0.5 cm5 mm <br />0.005 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
subshrub +  and cespitose +