Sesuvium mezianum (K. Müll.) Bohley & G. Kadereit, comb. nov.

Cypselea meziana K. Müll., Bot. Jahrb. Syst. 42 (2–3, Beibl. 97): 72. 1908.— TYPE: PARAGUAY. Near Asunción, lowlands along Paraguay River, 1875, B. Balansa 2263 (holotype: G 00102877 digital image!).

Creeping, perennial herb; shoots up to 0.4 m long, often rooting at nodes. Bladder cells not seen. Leaves obovate to oblanceolate 5–7 mm long, 2–3 mm wide; petioles short (1– 3 mm); lateral flaps distinctly auriculate with entire margins. Flowers 3–5 mm long, (greenish-) white, pendant, pedicellate (pedicels 1–2(–3) mm). Stamens 3. Ovary with 3 carpels. Fruit a circumscissile capsule. Seeds not seen.

Distribution and Habitat — The species is apparently endemic to Paraguay. It grows on saline soil.

Notes — Of the three species formerly classified as Cypselea, this one shows the highest resemblance to other Sesuoium species in morphology and ecology (perennial habit, salt tolerance). Only a digital image of the type was seen.