Hydnophytum ramispinum Merr. & L.M.Perry

25. Hydnophytum ramispinum Merr. & L.M.Perry View in CoL — Fig. 28 View Fig ; Map 4 View Map 4

Hydnophytum ramispinum Merr.& L.M.Perry (1945) 22. — Type: Brass 12858 (lectotype selected here A; iso L), Papua Province, Idenburg River , 6 km southwest of Bernhard Camp, Feb. 1939 .

Tuber spherical to cylindrical-ellipsoid, to 28 by 8 cm; smooth, or with irregularly branched spines. Stems several, pendent to upcurved, to 40 cm or more. Internodes (0.5–)1–5 by 0.1–0.4 cm. Leaves scattered, spreading. Lamina narrow linear, linear oblong to linear-ovate, and then broadest at 1/3 length; 1.1 by 0.2 to 5 by 1.4 (4 by 0.15) cm. Inflorescences paired, sessile. Flowers [7] heterostylous. Calyx 1 mm, entire or with a ciliate margin. Corolla tube 1.5 mm, with a ring of hairs towards the mouth, lobes 1–1.5 mm. Short-styled flowers with anthers to 0.8 mm, exserted from tube; pollen 3-porate, 46 μm, brochi 1 μm; stigma not lobed, at level of anthers. Long-styled flowers with anthers to 0.5 mm, at mouth of tube; pollen 42 μm, brochi 1 μm; stigma 2-lobed, exserted above anthers. Fruit and pyrenes unknown.

Ecology & Habitat — Forest, 100–1 420 m. Tuber with or without ants.

Distribution — Indonesia (Papua Province) and Papua New Guinea.

Conservation status — Near Threatened (NT). Whilst probably Vulnerable in some parts of its range, this taxon is widespread across much of the north coast of New Guinea with herbarium collections indicating 5 locations (subpopulations). Other information: georeferenced collections 10, AOO 12 500 km 2 (using an auto-value cell width of 50 km), EOO c. 44 000 km 2.

Notes — This species is characterised by its narrow linear-ovate leaves. The type is unusual for Hydnophytum in that it possesses stiff, branched spines, a feature found in only one other species ( H. confertifolium [18]). Although the remaining collections all lack spines, the leaf shape and flower characters are constant.

The Docters van Leeuwen collections (9980, 10279 & 10359) come from low altitudes in the Rouffaer (Tariku) river valley (175 m), whilst the remainder are from 1 000–1 400 m. These collections differ in their ciliate-margined calyx.

Hydnophytum valetonii [26] which is found on the southern side of the central Papua Province highlands, differs in its dimorphic leaves, these being smaller on the side branches than on the main stem. Leaf outlines of the two species are mapped.