Hymenoxys ambigens

(S. F. Blake) Bierner

Sida 16: 6. 1994.

Common names: Pinaleno Mountains rubberweed
EndemicConservation concern
Basionym: Plummera ambigens S. F. Blake J. Wash. Acad. Sci. 19: 276, fig. 1a–i. 1929
Treatment appears in FNA Volume 21. Treatment on page 438. Mentioned on page 435, 436.

Perennials, 30–150 cm (polycarpic, with sparingly branched, woody caudices). Stems 1–3, usually purple-red-tinted proximally, branched distally, glabrous or ± hairy. Leaves: blades simple or lobed (lobes 3–19+), glabrous or sparsely hairy, glanddotted; mid leaves lobed (lobes 3–19+, terminal lobes 0.7–1.3 mm wide). Heads 25–400+ per plant, in paniculiform to corymbiform arrays. Peduncles 0.4–2 cm, glabrous or ± hairy. Involucres campanulate to narrowly campanulate, 5–7.5 × 2.2–4.5 mm. Phyllaries in 2 series, unequal; outer 3–5, basally connate 1/2–3/4 their lengths, obovate to oblanceolate, 4–6 mm, apices acuminate, acute, obtuse, or rounded; inner 3–5, obovate to oblanceolate, 2.5–4.5 mm, apices acuminate, acute, obtuse, or rounded, sometimes mucronate. Ray-florets 3–5; corollas yellow, extending beyond phyllaries, 3.4–6 × 1.7–4 mm. Disc-florets 6–15 (functionally staminate); corollas 3–4 mm. Cypselae obconic, 1.7–3.5 mm (hairy, hairs straight or wavy); pappi 0, or of 2–6 ± lanceolate scales 1–2.5 mm.

Discussion

Varieties 3 (3 in the flora).

Selected References

None.

Key

1 Apices of inner phyllaries acuminate to mucronate; pappus scales 3–6 (sometimes 0 on disc florets); hairs on cypselae usually straight, sometimes slightly wavy; Arizona, Mescal, Pinaleno, and Santa Teresa mountains Hymenoxys ambigens var. ambigens
1 Apices of inner phyllaries rounded or obtuse to weakly acute or mucronate; pappus scales 0 or 2–4; hairs on cypselae moderately to strongly wavy; Arizona or New Mexico > 2
2 Plants 30–150 cm; outer phyllaries 3–4; hairs on cypselae strongly wavy; Arizona, Chiricahua, Dos Cabezas, Dragoon, Little Dragoon, and Mule Mountains Hymenoxys ambigens var. floribunda
2 Plants 30–40+ cm; outer phyllaries 5; hairs on cypselae moderately wavy; New Mexico, Animas and Peloncillo mountains Hymenoxys ambigens var. neomexicana
... more about "Hymenoxys ambigens"
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
Mark W. Bierner +
(S. F. Blake) Bierner +
decurrent +
Plummera ambigens +
hairy +  and glabrous +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
Pinaleno Mountains rubberweed +
0.34 cm3.4 mm <br />0.0034 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.17 cm1.7 mm <br />0.0017 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
hairy +  and glabrous +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +  and N.Mex. +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
discoid +  and radiate +
in paniculiform to corymbiform arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.6 cm6 mm <br />0.006 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
0.5 cm5 mm <br />0.005 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
campanulate;narrowly campanulate +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
obovate +  and oblanceolate +
unequal +  and subequal +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
2-carpellate +
persistent +
hairy +  and glabrous +
0.4 cm4 mm <br />0.004 m <br /> (2 cm20 mm <br />0.02 m <br />) +
28 +  and 50 +
bearing subulate enations +, hairy +  and bristly +
pitted +  and smooth +
conic;ovoid;conic;ovoid;hemispheric +
2 +  and 6 +
lanceolate +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
exalbuminous +
subequal;unequal +
Endemic +  and Conservation concern +
purple-red-tinted +
1 +  and 3 +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Dugaldia +  and Plummera +
Hymenoxys ambigens +
Hymenoxys +
species +
urceolate +  and campanulate +
dilated +
toothed +  and entire +
3 (?) +  and 5 (?) +
obovate +  and oblanceolate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
shrub +  and subshrub +