treatments/Malacothrix glabrata var. glabrata

From Botanical Knowledge
Jump to: navigation, search


Malacothrix glabrata   var. glabrata in A. Gray et al., Syn. Fl. N. Amer.. 1(2): 422. 1884.

Smooth desertdandelion


Annuals, (5–)10–40+ cm. Stems (1–)3–5+, ascending to erect, usually branched proximally and distally, glabrous or sparsely arachno-puberulent near bases (sometimes glaucous). Cauline leaves: proximal usually pinnately lobed (lobes 3–6+ pairs, usually filiform, subequal to unequal, apices acute), ultimate margins entire, faces glabrous or ± hairy (then usually glabrescent); distal reduced (usually pinnately lobed). Calyculi of 12–20+, lanceolate to linear bractlets, hyaline margins 0.05–0.2 mm wide (abaxial faces often ± densely white-hairy). Involucres campanulate to hemispheric, 9–17 × 4–7 mm. Phyllaries 20–25+ in 2–3 series, lance-linear to linear, hyaline margins 0.05–0.3 mm wide, faces usually glabrous, abaxial sometimes ± white-hairy. Receptacles bristly. Florets 31–139; corollas usually pale yellow, sometimes white, 15–23+ mm; outer ligules exserted 9–15+ mm. Cypselae ± cylindro-fusiform (sometimes weakly 5-angled), 2–3.3 mm, ribs extending to apices, usually ± equal; persistent pappi of 0–12+, blunt to acute teeth plus 1–2(–5) bristles. Pollen 70–100% 3-porate. 2n = 14.

Flowering Mar–Jul. coarse soils in open areas , or among shrubs , creosote bush scrublands , amsinckia , artemisia , and atriplex-larrea associations , joshua tree woodlands ;0–1800 m;Ariz.; Calif.; Idaho; Nev.; N.Mex.; Oreg.; Utah;Mexico (Baja California).; Mexico (Sonora).;

Malacothrix glabrata grows in the Mojave, Great Basin, and Sonoran deserts in California and the Intermountain region in Arizona, Nevada, Oregon, and Utah.