Eriocaulon hamiltonianum Mart.

Annual herbs, tufted. Leaves crowded into a basal rosette, linear-lanceolate, 4–5(–6) × 0.2–0.4 (–0.5) cm, glabrous, acute or obtuse. Scapes numerous, to 12 cm long, glabrous, 4-ribbed. Sheaths to 3.5 cm long, glabrous, obtuse. Heads globose to ovoid, 3.5 × 3–4 mm, grey. Receptacle cylindrical, pilose. Involucral bracts reflexed, oblong to lanceolate, 1.5 × 0.75 mm, subacute, glabrous, chartaceous, pale brown. Floral bracts elliptic-oblanceolate, 1.5–2 × 0.8–1 mm, acute, chartaceous, glabrous, blackish brown. Male flowers: pedicellate, ca. 0.5 mm long; sepals 2, free, oblanceolate-falcate, 1 × 0.5 mm, acuminate, glabrous, black; stipe of the corolla ca. 0.5 mm long; petals 3, minute; stamens 6, anthers black. Female flowers: pedicellate, 0.25 mm long; sepals 2 or rarely 3, free, subequal, ca. 1.25 mm long, the middle one (if present) minute, linear, acuminate, glabrous, black; petals 3, subqual, linear, 0.75–1 mm long, acute, glabrous, hyaline without a black gland; stipitate between sepals and petals; ovary stalked, 3-locular, stigmas 3. Seeds ovoid-ellipsoid, 0.5 × 0.3 mm, acute or apiculate, pale yellow; cells of seed coat transversely elongate, aligned in vertical rows; cells hexagonal; appendages in the form of pair of continuous ribbon-like bands from transverse and vertical radial walls conforming to its length.