Cotula filifolia Thunb.

Upright annual herb. Stems 30-150 mm, glabrous, herbaceous, 0.5-1.5 mm wide. Leaves alternate, spreading, entire, sometimes once-pinnate, 0.5-25.0 x 1.0-2.0 mm, base dilated, forming a prominent sheath around the stem, sheath 1.0-3.0 mm long; lobes linear, 0.5-25 x 1.0-1.8 mm, ± terete, leathery, dark green, glabrous, apices acute, margins entire. Capitula heterogamous, disciform, solitary, terminal, pedunculate peduncle glabrous to sparsely hairy, 30.0-75.0 mm. Involucre hemispherical, 3.0-6.0 x 4.0-6.0 mm, 1-seriate, bracts broadly ovate tapering to an obtuse apex, 2.0-5.0 x 2.0-4.0 mm, glabrous, green, opaque, apex and margin scarious, four to six veined, secondary venation prominent. Receptacle flat, epaleate; pedicels linear, pedicels 0.4-2.0 mm at anthesis, uniform, attaching to floret apically. Disciform florets female, ca. 6, in single outer series, corolla absent, style 0.2 mm, ovary marginally winged, usually with stout flat hairs on inner face. Disc florets bisexual, ca. 20 to 40, corolla 0.95-1.1 mm long, yellow, oblong, tube not draped basally over ovary apex, longitudinal resin canals present, limb slightly wider than tube, 4 lobed; lobes triangular, upright to spreading, dorsally tuberculate, slightly 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, usually with stout flat hairs on inner face. Cypselas heteromorphic; disciform cypselas ovoid, ca. 1.4 x 1.0 mm, marginally winged, wing ½ width of ovary, base cordate, inner face usually with stout flat hairs on inner face; disc cypselas ovoid, ca. 1.6 x 0.9 mm, marginally winged, wing 1/3 width of ovary, inner face usually with stout flat hairs.