Coarse herbaceous to somewhat woody, sparingly branched vines; stems brownish, terete to slightly hexagonal, striate, minutely puberulous, usually fistulose. Leaves opposite; blades broadly ovate, to 15 cm long and 8 cm wide, the base broadly rounded, the margins entire, the apex abruptly narrow-acuminate, sometimes apiculate, the surface slightly puberulous to glabrate with small glandular punctations, 2-3 pairs of prominent secondary veins arching outward and upward from lower fifth of the blade, the tertiary veins regularly transverse; petioles slender, mostly 2-6 cm long. Inflorescence a panicle with glomerulate-corymbose secondary and tertiary branches, the branches minutely puberulous, the ultimate branches 0-1 mm long. Heads 7-8 mm high; subinvolucral bract linear-lanceolate, minute, 0.3-0.8 mm long, minutely puberulous; involucral bracts short-oblong with rounded tips, ca. 2.0-2.5 mm long including fused swollen bases, ca. 0.8 mm wide, whitish-puberulous and minutely glandular-punctate on the outer surface; corolla white, ca. 4.5 mm long, narrowly funnelform, the tube indistinct, the lobes short, about half again as long as wide with few glands and short hairs on outer surface, the corolla cells quadrate to short-oblong, 20-30 aL wide; anther appendages firm, rather oblong, slightly longer than wide; style base glabrous, the style appendages with short papillae. Achenes 5-ribbed, ca. 2 mm long, the sides with scattered, short, often distorted bristles; pappus of 40-50 slender slightly scabrous bristles in 1 series, the apices slightly to distinctly enlarged.
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