Herbs annual. Roots conic or spinose. Stems densely branched at base, 2--4 cm; branches slender, ca. 0.5 mm in diam., retrorsely white pubescent in 2 lines. Petiole absent or short; leaf blade linear or linear-lanceolate, 4--5 × 1--2 mm, tuberculate, 1--3-veined, midvein impressed proximally. Pedicel 3--5.5 mm. Sepals 5, narrowly elliptic, hooded, 1.5--3 × 0.5--1 mm, villous abaxially, 3-veined, midvein impressed, lateral veins inconspicuous, base broadened, margin narrowly membranous, apex obtuse or acute. Petals absent. Stamens 2 or 3, ca. 1 mm. Capsule ellipsoid-ovoid, 2.5--3 mm, deeply 4-valved; valves ellipsoid, ca. 1 mm in diam. Seeds brown, subglobose, ca. 0.6 mm in diam., narrowly and irregularly parallel striate.