Stems erect, branched, stout, usually 1–3 m. Leaves: petiole 1/2 length of blade; blade lanceolate or narrowly lanceolate to linear, to 20 × 4 cm, base narrowly cuneate, margins entire, plane to slightly undulate, apex acute to acuminate. Inflorescences mostly terminal, narrow spikes or thyrses, usually interrupted, linear. Bracts: of pistillate flowers 1.5 mm; of staminate flowers with midribs not prominent, scarcely excurrent, shorter than 1 mm. Pistillate flowers: tepals absent or 1–2 and rudimentary; style branches ± erect; stigmas 3–5. Staminate flowers: tepals 5, without prominent midribs, equal, 2.5–3 mm, apex obtuse to indistinctly mucronulate in outer tepals; stamens 3–5. Utricles often black, with 3(–5) longitudinal ridges corresponding to 3–5 style branches, ovoid or obovoid, 2.5–4 mm (exceeding tepals, when present), somewhat fleshy, smooth (slightly rugose, especially in herbarium specimens). Seeds reddish brown to dark brown, 2–3 mm diam., shiny.
