6. Hydnophytum tortuosum Becc. — Fig. 7; Map 1

Hydnophytum tortuosum Becc. (1884) 124; (1885) 141, t. 37: 1–5. — Type: Beccari 185 (lectotype selected here FI; iso K), New Guinea, West Papua Province, Sorong .

Tuber spherical, to 20 cm across, smooth, otherwise unknown. Stems numerous, to 60 cm long, little branched; internodes 1–6 by 0.1–0.3 cm, round; nodes slightly swollen. Lamina obovate; 3 by 1.6 to 4.5 by 2.5 cm; apex rounded-acute, base cuneate; veins 3–5; leaves tending to dry crinkled. Petiole 0–0.3 cm; stipules triangular, 0.1 cm, caducous. Inflorescence an area of socket-like depressions across one axil of each node, and to sides of petiole. Flowers [2]?heterostylous. Calyx 1.5 mm. Corolla tube 2 mm, lobes 2 mm, a ring of hairs at mouth of tube. Anthers within throat or exserted, 1 mm long. Pollen 44 (40–48) µm diam. Stigma 2-fid, lobes long, above anthers. Fruit and pyrenes immature.

Ecology & Habitat — Mangrove forest to lowland forest, sea level to 300 m. Tuber inhabited by ants.

Distribution — New Guinea (West Papua Province).

Conservation status — Vulnerable (VU) under criteria D2 with only two locations known c. 120 km apart.

Note — The specimens included here in this species are somewhat varied, but each exhibits an inflorescence structure identical to that illustrated by Beccari (1885: t. 37), and all are found in a limited geographical area, see Map 1. The inflorescence shows similarities to those of H. ovatum [4] and H. spathulatum [5], although in these latter two species they are developed into prominently swollen nodes.