Geraea

Torrey & A. Gray

Proc. Amer. Acad. Arts 1: 48. 1847.

Common names: Desert-sunflower
Etymology: Greek geraios, old, alluding to white-haired involucre of Geraea canescens
Treatment appears in FNA Volume 21. Treatment on page 122. Mentioned on page 65, 66, 119.
Revision as of 20:11, 5 November 2020 by imported>Volume Importer
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Annuals or perennials, 10–100 cm. Stems erect, branched (branches ascending). Leaves basal and cauline; alternate; sessile or petiolate; blades (3-nerved) elliptic, lanceolate, oblanceolate, oblong, or ovate, bases auriculate or tapering, margins entire or toothed, faces ± canescent or glandular-puberulent to stipitate-glandular. Heads radiate or discoid, borne singly or in open, paniculiform arrays (peduncles usually longer than involucres). Involucres hemispheric, 7–15 mm diam. Phyllaries persistent, 20–30+ in 2–3+ series (distinct, narrowly lanceolate to linear or narrowly lance-oblong to lance-ovate, subequal to unequal, outer shorter). Receptacles convex, paleate (paleae ± conduplicate, folded around and falling with cypselae). Ray florets 0 or 10–21, neuter; corollas yellow. Disc florets 60–200+, bisexual, fertile; corollas yellow, tubes shorter than gradually to abruptly expanded throats, lobes 5, triangular. Cypselae (black) strongly compressed, narrowly cuneate (margins ± white, long-ciliate, faces ± hairy); pappi persistent, of 2 awns or subulate scales. x = 18.

Distribution

sw United States, nw Mexico.

Discussion

Species 2 (2 in the flora).

Selected References

None.

Key

1 Annuals; leaves sessile or petiolate, bases of blades tapering to wings, faces ± canescent; phyllaries narrowly lanceolate to linear, apices acute (margins shaggy-ciliate); ray florets 10–21 Geraea canescens
1 Perennials; leaves sessile, bases of blades ± auriculate, faces glandular-puberulent; phyllaries narrowly lance-oblong to lance-ovate, apices obtuse (faces densely glandular-puberulent); ray florets 0 Geraea viscida
... more about "Geraea"
Curtis Clark +
Torrey & A. Gray +
Desert-sunflower +
sw United States +  and nw Mexico. +
Greek geraios, old, alluding to white-haired involucre of Geraea canescens +
Proc. Amer. Acad. Arts +
Undefined (tribe Undefined) subtribe Enceliinae +, Undefined (tribe Undefined) subtribe Engelmanniinae +, Undefined (tribe Undefined) subtribe Spilanthinae +, Undefined (tribe Undefined) subtribe Verbesininae +  and Undefined (tribe Undefined) subtribe Zinniinae +
Asteraceae (tribe Heliantheae) subtribe Ecliptinae +