Tree 5-8 m. Leaves thickly membranous, (elliptic-)oblong, (18—)25—38 by (6-)7-13 cm, base short to long-attenuate, apex attenuate-acuminate; Inflorescences below the leaves; Flowers 2-5 together in male and female, with loose hairs (0. l-)0.2-0.3 mm long, in female glabrescent towards apex; Fruits not seen.
Asia-Tropical, Morobe Prov present, Northern Papua New Guinea present, Sepik present
Malesia: northern Papua New Guinea (Sepik, Morobe Prov.).
1 Horsfieldia ampliformis is close to H. ampla, of which no material has been seen. According to the description the latter differs by the more elongate, possibly glabrous perianths, 4 by 2 mm, the androecium with 20 thecae, and the glabrescent inflorescences. The two species have a peculiar long-stalked androecium and larg, male inflorescences. Horsfieldia ampla was collected at only 200-400 m altitude. 2 Known only from a male and a female flowering specimen. The perianths of the female specimen, Craven & Schodde 1463 (Morobe Prov.), are glabrescent in the upper half; it could be H. ampla. Moreover, as the hairs on the leaf buds are slightly shorter than those of the male specimen, this specimen is difficult to distinguish from the variable and widespread H. laevigata.