Chrysogonum

Linnaeus

Sp. Pl. 2: 920. 1753.

,

Gen. Pl. ed. 5, 391. 1754.

Etymology: Greek chrysos, gold, and gonos, seed, apparently alluding to the bright yellow, hemispheric capitula or to the fertile cypselae from the cypsela-complexes of the ray florets
Treatment appears in FNA Volume 21. Treatment on page 74. Mentioned on page 65.
 TaxonIllustrator 
FNA21 P11 Lindheimera texana.jpegChrysogonum virginianum var. brevistolon
Lindheimera texana
Silphium laciniatum
Linny Heagy
Barbara Alongi
Yevonn Wilson-Ramsey

Perennials, 2–30 (–50) cm (aerial stems from fibrous-rooted rhizomes to 5 cm). Stems erect to erect-ascending (flowering) or prostrate (vegetative stolons), branched from bases or ± throughout (villous). Leaves basal and cauline; opposite; petiolate; blades elliptic-ovate to deltate-ovate, bases cordate or truncate to cuneate, margins crenate, faces hairy. Heads radiate, borne singly or in pairs. Involucres cupulate-hemispheric, 7–10 mm diam. Phyllaries persistent (outer), 8–10 in 2 series (outer spreading, oblong-oblanceolate, foliaceous, inner erect, greenish, smaller, ± scarious). Receptacles flat to shallowly convex, paleate (paleae oblanceolate, scarious). Ray-florets 5 (–6), pistillate, fertile; corollas yellow. Disc-florets 25–50, functionally staminate; corollas yellow, tubes shorter than narrowly funnelform throats, lobes 5, deltate. Cypselae (blackish brown) strongly obflattened, obovoid to obovate (each basally adnate to 1 inner phyllary, 3 paleae, and 3 disc-florets, the “cypsela-complexes” falling as units); pappi persistent, coroniform (asymmetric). x = 16.

Distribution

e United States

Discussion

Species 1.

Each cypsela-complex includes an elaiosome (a fleshy, oil-bearing structure at the base of the phyllary) and two associated paleae. Ants carry cypsela-complexes into their underground nests, chew off the elaiosomes, and return the undamaged cypselae or complexes to the surface.

Chrysogonum virginianum has been divided into two species (e.g., J. K. Small 1933) or treated as a single species with two varieties (e.g., A. E. Radford et al. 1968; T. F. Stuessy 1977). Stuessy mapped many intermediates between two varieties, not only in the area of North Carolina and South Carolina where their ranges meet, but also practically throughout both their ranges. G. L. Nesom (2001) found three allopatric taxa, separated primarily by habit (production or not of stolons) and morphology of flowering stems. Plants treated here as C. virginianum var. australe might justifiably be treated at specific rank.

All three taxa of Chrysogonum are now used as garden plants and are sold in nurseries under horticultural names.

"broader" is not a number.

... more about "Chrysogonum"
not tailed +, rounded +  and obtuse +
connate +  and distinct +
subequal +
scarious +
usually ovate +  and lanceolate +
usually deltate +  and lanceolate +
spiciform +, racemiform +, paniculiform +, corymbiform +  and cymiform +
indeterminate +  and determinate +
Guy L. Nesom +
Linnaeus +
bristlelike +
coroniform +
truncate +  and cuneate +
compound +  and simple +
elliptic-ovate;deltate-ovate +
winged;ribbed;winged;ribbed +
tuberculate +  and rugose +
barbellulate +  and barbellate +
hairy +  and glabrous +
obovoid +  and obovate +
fertile +  and bisexual +
fertile +  and bisexual +
e United States +
Greek chrysos, gold, and gonos, seed, apparently alluding to the bright yellow, hemispheric capitula or to the fertile cypselae from the cypsela-complexes of the ray florets +
pistillate +, staminate +  and neuter +
winged +  and beaked +
dispersed +
in cymiform , corymbiform , paniculiform , racemiform or spiciform , arrays +  and singly +
indeterminate +
homogamous +  and heterogamous +
each +  and sessile +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
cupulate-hemispheric +
cauline +  and basal +
deltate +
dentate to pinnatifid or palmatifid +  and entire +
2-carpellate +
persistent +
coroniform +
8 +  and 10 +
unequal +  and subequal +
Sp. Pl. +  and Gen. Pl. ed. +
1753 +  and 1754 +
bearing subulate enations +, hairy +  and bristly +
flat;shallowly convex +
nesom2001b +  and stuessy1977b +
exalbuminous +
erect +  and erect-ascending or prostrate +
appendaged +  and truncate +
hirsutulous +  and glabrous +
papillate +
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 +
Chrysogonum +
Asteraceae (tribe Heliantheae) subtribe Ecliptinae +
cylindric +
shorter to longer than campanulate +
toothed +  and entire +
30 cm300 mm <br />0.3 m <br /> (50 cm500 mm <br />0.5 m <br />) +
2 cm20 mm <br />0.02 m <br /> (30 cm300 mm <br />0.3 m <br />) +
shrub +  and subshrub +