Cotula pusilla Thunb.

Upright, annual herb. Stems 5-15 mm, glabrous, herbaceous, 0.5-1.5 mm wide. Leaves alternate, spreading, ± terete, entire, once-pinnate or twice-pinnate, 6.0-35 x 2.0-6.0 mm; base dilated, forming a prominent sheath around the stem, sheath 1.0-4.0 mm long; lobes linear to ovate, 0.3-2.0 x 0.1-2.0 mm, flat, leathery, light to dark green, densely to sparsely hairy, apices acute, margins entire. Capitula heterogamous, disciform, solitary, terminal, pedunculate, peduncles glabrous to sparsely hairy, 5.0-15.0 mm. Involucre hemispherical, 2.0-6.0 x 3.0-9.0 mm, 1-seriate, bracts broadly elliptic, 2.0-4.0 x 1.0-2.0 mm, glabrous, purplish, opaque, apex and margins scarious, distinctly three veined, secondary venation obscure. Receptacle flat, epaleate; disciform pedicels linear, 0.15-1.0 mm at anthesis, uniform, pedicel attaching to floret apically. Disciform florets female, ca.4 to 6, in single outer series, corolla absent, style 0.45-0.6 mm, ovary marginally winged, with dense terete hairs on inner face. Disc florets bisexual, ca. 20 to 40, corolla 1.2-1.5 mm long, whitish, oblong, tube draped basally over ovary apex, longitudinal resin canals sometimes present, limb same width as tube, 4 lobed; lobes triangular, upright to spreading, dorsally tuburculate, glandular; anthers 0.5-1.2 mm long (including apical appendages), ecaudate, apical appendages ovate, acute; style terete with thickened base; branches truncate, papillate apically-dorsally; ovary marginally winged, dense terete hairs on inner face. Cypselas heteromorphic; disciform cypselas ovoid, ca. 1.7 x 1.4 mm, marginally winged, ± equal to width of ovary, base cordate, inner face with dense terete hairs; disc cypselas ovoid, ca. 1.2 x 0.6, marginally winged, wing width equal to ovary, with dense terete hairs.