Hydnophytum spathulatum Valeton

5. Hydnophytum spathulatum Valeton View in CoL — Fig. 6 View Fig ; Map 1 View Map 1

Hydnophytum spathulatum Valeton (1912a) t. 340. — Type: Smith s.n. (lectotype selected here BO 1360 ­ 120 ; iso BO 1360­119 ), Moluccas, Batjan Is , 2 Sept. 1900.

Tuber oblong to conical, to 25 by 10 cm, ridged, smooth or rough; spines unbranched, flexible, root-like or recurved, on ridges; entrance holes numerous. Stems several, arising from a large area around tuber apex, to 50 by 0.4 cm, little branched; internodes 1–5 by 0.1–0.3 cm, terete; spines rarely present at nodes. Lamina spathulate, 3 by 1.8 to 5.5 by 2.5 cm; apex rounded, base attenuate; leathery to thin; midrib not prominent, veins obscure. Petiole 0–0.5 cm, stipules c. 0.1 cm, soon falling. Inflorescence a mass of tightly grouped sockets forming a prominent swelling at each node; bracts small, papery. Flowers [2]?heterostylous. Calyx c. 0.2 mm. Corolla tube to 2.5 mm; lobes 1–1.5 mm; with a broad band of short hairs at level of anthers at mouth of tube. Anthers 1 mm, at mouth of tube. Pollen 3-porate, 53 (50–57) µm, brochi <1 µm across; vesicles prominent. Stigma bifid, exserted. Fruit globose, red. Pyrenes obovoid, 3.5 by 1.5 mm; the flattened surface adpressed to the other pyrene c. 2.8 mm long, the rounded-acute apex projecting freely away from the other pyrene.

Ecology & Habitat — Forest, from sea level to 300 m. Tuber inhabited by ants.

Distribution — Indonesia, Maluku Province.

Conservation status — Vulnerable (VU) under criteria D2. Known from four collections, one from each island in the north Moluccas. Since EOO and AOO measures are inappropriate, criteria D2 is utilised.

Notes — The inflorescence of this species is similar to that of H. ovatum [4], although the leaves are very different and it is more widely distributed in the north Moluccas.

The specimen De Vogel 4130 from Obi Island is placed here with reservation. The leaves are lanceolate and finely attenuated at each end, reaching 10 by 1.5 cm.