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Bigelow's rubberweed

rincon rubberweed, rincon rubberweed or bitterweed

Habit Perennials, 20–70 cm (polycarpic, often with sparingly branched, woody caudices). Perennials, 30–100 cm (polycarpic; sometimes with sparingly branched, woody caudices).
Stems

1–5, green throughout or purple-red-tinted distally to throughout, usually unbranched distally, ± hairy (often tomentose proximally).

1(–3), green throughout or purple-red-tinted proximally, branched distally, ± hairy.

Leaves

blades usually simple, rarely lobed (lobes 3), glabrous or ± hairy, eglandular or sparsely gland-dotted (basal leaf bases ± long-villous-woolly);

mid leaves usually simple, rarely lobed (lobes 3, terminal lobes 1.5–3 mm wide).

blades simple or lobed (lobes 3–17), glabrous or sparsely hairy, gland-dotted;

mid leaves lobed (lobes 5–11, terminal lobes 0.8–2 mm wide).

Peduncles

(1.5–)6–20(–29) cm, ± hairy, densely tomentose distally near involucres.

2.5–7 cm, ± hairy.

Involucres

hemispheric to broadly campanulate, 13–20 × 23–32 mm.

campanulate, 8–10 × 9–12 mm.

Ray florets

13–15;

corollas yellow, 13–26 × 5.4–9.5 mm.

5–8;

corollas yellow, 14–18 × 7–12 mm.

Disc florets

100–250+;

corollas 5.7–7.4 mm.

30–100+;

corollas 3.5–4.3 mm.

Phyllaries

in 2 series, unequal;

outer 13–19, basally connate only slightly to 1/5 their lengths, lanceolate to narrowly lanceolate to obovate to oblanceolate, 7–11 mm, apices acuminate to acute;

inner 13–18, narrowly lanceolate to oblanceolate, 8.5–12.6 mm, apices aristate.

in 2 series, unequal;

outer 5(–8), basally connate 1/3–1/2 their lengths, obovate to ovate, 6–7 mm, apices acuminate;

inner 6–8, obovate, 6.5–8 mm, apices mucronate.

Heads

1–5 per plant, usually borne singly, sometimes in paniculiform arrays.

5–50+ per plant, in paniculiform to corymbiform arrays.

Cypselae

narrowly obpyramidal, 4.2–4.7 mm;

pappi of 9–11(–15) obovate to oblanceolate, often aristate scales 4.7–7.3 mm.

obpyramidal, 2.5–3.9 mm;

pappi of 5–6 obovate, sometimes aristate, scales 1.2–2.5 mm.

2n

= 30.

= 30.

Hymenoxys bigelovii

Hymenoxys quinquesquamata

Phenology Flowering May–Jun. Flowering (Jun–)Jul–Sep(–Oct).
Habitat Roadsides, edges of juniper-pine and pine forests Open areas, edges of pine-oak forests
Elevation 1300–2500 m (4300–8200 ft) 1500–2500 m (4900–8200 ft)
Distribution
from FNA
AZ; NM
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ
[BONAP county map]
Discussion

Hymenoxys quinquesquamata is known from southern Arizona, mostly Huachuca Mountains.

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

Source FNA vol. 21, p. 440. FNA vol. 21, p. 441.
Parent taxa Asteraceae > tribe Heliantheae > subtribe Gaillardiinae > Hymenoxys Asteraceae > tribe Heliantheae > subtribe Gaillardiinae > Hymenoxys
Sibling taxa
H. ambigens, H. brachyactis, H. brandegeei, H. cooperi, H. grandiflora, H. helenioides, H. hoopesii, H. jamesii, H. lemmonii, H. odorata, H. quinquesquamata, H. richardsonii, H. rusbyi, H. subintegra, H. texana, H. vaseyi
H. ambigens, H. bigelovii, H. brachyactis, H. brandegeei, H. cooperi, H. grandiflora, H. helenioides, H. hoopesii, H. jamesii, H. lemmonii, H. odorata, H. richardsonii, H. rusbyi, H. subintegra, H. texana, H. vaseyi
Synonyms Actinella bigelovii
Name authority (A. Gray) K. F. Parker: Madroño 10: 159. (1950) Rydberg: in N. L. Britton et al., N. Amer. Fl. 34: 114. (1915)
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