Hymenoxys subintegra

Cockerell

Bull. Torrey Bot. Club 31: 480. 1904.

Common names: Arizona rubberweed
Endemic
Synonyms: Actinea subintegra (Cockerell) S. F. Blake
Treatment appears in FNA Volume 21. Treatment on page 441. Mentioned on page 435, 436.

Biennials or perennials, 30–60 cm (monocarpic; sometimes with sparingly branched, woody caudices). Stems 1 (–5), green throughout or sometimes purple-red-tinted proximally, branched distally, usually densely sericeous. Leaves: blades simple or lobed (lobes 3), usually densely sericeous, glanddotted; mid leaves simple or lobed (lobes 3, terminal lobes 1.8–3.5 mm wide). Heads 10–85+ per plant, in paniculiform to corymbiform arrays. Peduncles 3–9 cm, usually densely sericeous. Involucres hemispheric to campanulate, 8–10 × 10–13 mm. Phyllaries in 2 series, unequal; outer 10–14 (–18), basally connate 1/4–1/2 their lengths, lanceolate, obovate, or ovate 5–7 mm, apices acuminate to acute; inner phyllaries 13–16 (–22), obovate, 4–5 mm, apices mucronate. Ray-florets 10–16; corollas yellow, 10–15 × 4.5–6.5 mm. Disc-florets 50–100+; corollas 3.5–4 mm. Cypselae narrowly obpyramidal, 2.1–3 mm; pappi of 5 (–6) obovate, aristate scales 2.5–3 mm. 2n = 30.


Phenology: Flowering (Jun–)Jul–Aug(–Sep).
Habitat: Roadsides, open areas, edges of forests
Elevation: 2100–2800 m

Discussion

Hymenoxys subintegra grows mainly on the Kaibab Plateau north of the Grand Canyon in Arizona and in western Kane County, Utah.

Selected References

None.

Lower Taxa

None.
... more about "Hymenoxys subintegra"
not tailed +, rounded +  and obtuse +
connate +  and distinct +
mucronate;acuminate;acute +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
paniculiform +  and corymbiform +
indeterminate +  and determinate +
Mark W. Bierner +
Cockerell +
decurrent +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
Arizona rubberweed +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
0.35 cm3.5 mm <br />0.0035 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.45 cm4.5 mm <br />0.0045 m <br /> (0.65 cm6.5 mm <br />0.0065 m <br />) +
hairy +  and glabrous +
obpyramidal +
fertile +  and bisexual +
fertile +  and bisexual +
Ariz. +  and Utah. +
2100–2800 m +
hairy +  and glabrous +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
Roadsides, open areas, edges of forests +
discoid +  and radiate +
in paniculiform to corymbiform arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.4 cm4 mm <br />0.004 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
0.6 cm6 mm <br />0.006 m <br /> (3.2 cm32 mm <br />0.032 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
hemispheric;campanulate +
1 cm10 mm <br />0.01 m <br /> (1.3 cm13 mm <br />0.013 m <br />) +
sessile +  and petiolate +
cauline +  and basal +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
ovate +, obovate +  and lanceolate +
unequal +  and subequal +
0.5 cm5 mm <br />0.005 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
2-carpellate +
persistent +
3 cm30 mm <br />0.03 m <br /> (9 cm90 mm <br />0.09 m <br />) +
Flowering (Jun–)Jul–Aug(–Sep). +
28 +  and 50 +
Bull. Torrey Bot. Club +
bearing subulate enations +, hairy +  and bristly +
pitted +  and smooth +
conic;ovoid;conic;ovoid;hemispheric +
aristate +  and obovate +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
exalbuminous +
subequal;unequal +
1 (?) +  and 5 (?) +
green throughout or sometimes purple-red-tinted +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
Actinea subintegra +
Hymenoxys subintegra +
Hymenoxys +
species +
urceolate +  and campanulate +
dilated +
toothed +  and entire +
perennial +  and biennial +
30 cm300 mm <br />0.3 m <br /> (60 cm600 mm <br />0.6 m <br />) +
shrub +  and subshrub +