Stem up to 100 cm, floating. Leaves very long, floating, plano-convex or semi-terete, not inflated at base. Inflorescence elongate, often branched at base; branches with 2-3 female capitula and often without male capitula; main axis with 3-7 female capitula and 2-6 male capitula. Lower bracts longer than inflorescence, usually floating. Capitula remote, axillary, sessile, or lower female capitula pedunculate. Fruit ovoid, dark grey to dark brown, pedicellate; style abruptly deflexed from base.