Hydnophytum lucidulum Valeton

44. Hydnophytum lucidulum Valeton View in CoL — Fig. 47 View Fig

Hydnophytum lucidulum Valeton (1927) 137. — Papua New Guinea, Schlechter 19628 (lectotype selected here L; iso BM, G, K), Morobe Province, Dischore .

Tuber size and appearance unknown. Stems several, much branched, to 40 cm or more. Internodes 0.5–5 by 0.2–0.5 cm; rounded to angular. Lamina lanceolate to ovate-lanceolate, 2.5 by 1–6 by 2.5 cm; apex acute to blunt; base cuneate; midrib prominent above and below; veins c. 5 obscure; leathery; margin recurved. Petiole 0.2–0.5 cm; stipules 0.1 cm, triangular, papery, caducous. Inflorescence paired peduncles to 0.5 cm. Bracts minute. Flowers [2]?heterostylous. Calyx entire 1.5 mm. Corolla tube 2 mm; lobes 1 mm, with a ring of hairs 2/3rds way up tube. Anthers <1 mm; at mouth of tube. Pollen 3-colporate, 44 μm, walls thick. Stigma 2-lobed, below ring of hairs, style 1 mm. Fruit 4 mm, with prominent calyx remains. Pyrenes ovoid, 3 by 1.5 mm.

Ecology & Habitat — Forest, 350–1 650 m.

Distribution — Papua New Guinea (Central & Morobe Provinces)

Conservation status — Endangered (EN) under criteria B1ab(iii)+2ab(iii). Other information: AOO 342 km 2 (using an auto-value cell width of 14 km), EOO 567 km 2.

Note — The small lanceolate leaves with prominent midribs both above and below are quite unlike those of H. moseleyanum [14] with which it shares shortly pedunculate inflorescences. Although the collections imply a large geographic spread, it remains known from just two locations some 140 km apart.