Gamochaeta coarctata

(Willdenow) Kerguélen

Lejeunia 120: 104. 1987.

Common names: Elegant cudweed
Basionym: Gnaphalium coarctatum Willdenow Sp. Pl. 3: 1886. 1803,
Synonyms: Gamochaeta spicata Cabrera
Treatment appears in FNA Volume 19. Treatment on page 435. Mentioned on page 432, 436.

Winter annuals or biennials, 15–35(–50) cm; fibrous-rooted. Stems decumbent-ascending, white-pannose (tomentum usually sheath-like). Leaves basal and cauline, basal present (in rosettes) at flowering, blades spatulate to oblanceolate-obovate, (1.5–)3–8(–12) cm × 6–15(–22) mm (gradually or little smaller distally, slightly succulent, margins often crenulate on drying), faces bicolor, abaxial closely white-pannose, adaxial glabrous or glabrate. Heads initially usually in dense, continuous spiciform arrays 2–20 cm × 10–14 mm (pressed), later branched, interrupted. Involucres cylindro-campanulate, 2.5–3 mm, bases glabrous. Phyllaries in 4–5 series, outer (purplish or rosy) elliptic-obovate to broadly ovate-elliptic, lengths 1/3–1/4 inner, apices rounded to obtuse, inner oblong, laminae brown-hyaline, apices rounded to obtuse or blunt, apiculate. Florets: bisexual 2–3; all corollas usually purplish distally. Cypselae (tan) 0.5–0.6 mm. 2n = 28, 40.

Phenology: Flowering Apr–Jun.
Habitat: Ditches, low roadsides, sidewalk cracks, shaded spots around buildings, other shaded, moist habitats
Elevation: 0–150 m



Introduced; Ala., Ark., Calif., Fla., Ga., La., Miss., N.C., S.C., Tex., Va., South America, also introduced in Mexico, West Indies, Europe, Asia, Pacific Islands (New Zealand), Australia.


Gamochaeta coarctata is native to South America and is also introduced in Mexico. R. K. Godfrey (1958) identified specimens of G. coarctata as Gnaphalium spicatum Lamarck. Some specimens from the flora area were misidentified by G. L. Nesom (1990f) as Gamochaeta americana (Miller) Weddell, which was described from Jamaica; it is widespread in Central America and Mexico, and has not been observed in the flora area.

Selected References


Lower Taxa

... more about "Gamochaeta coarctata"
Guy L. Nesom +
(Willdenow) Kerguélen +
Gnaphalium coarctatum +
Elegant cudweed +
Ala. +, Ark. +, Calif. +, Fla. +, Ga. +, La. +, Miss. +, N.C. +, S.C. +, Tex. +, Va. +, South America +, also introduced in Mexico +, West Indies +, Europe +, Asia +, Pacific Islands (New Zealand) +  and Australia. +
0–150 m +
Ditches, low roadsides, sidewalk cracks, shaded spots around buildings, other shaded, moist habitats +
Flowering Apr–Jun. +
Introduced +  and Illustrated +
Gamochaeta spicata +
Gamochaeta coarctata +
Gamochaeta +
species +