Tree 10-21 m. Leaves thinly chartaceous, (elliptic-)oblong, 8-20 by 2.5-7.5 cm, base attenuate, apex bluntish to acute-acuminate; Inflorescences glabrescent or with scattered scale-like hairs less than 0.1 mm; Fruits solitary or up to 6 per infructescence, ellipsoid, apex rounded to subacute, base ± rounded, 2 by 1.4-1.5 cm, glabrous, drying dark brown, without or with only small tubercles or lenticels;
Asia-Tropical, Bird's Head present, Geelvink Bay present, Jayapura present, Northern Papua New Guinea present, Papua Barat present, West Sepik Prov present, northern part of New Guinea present
Malesia: northern part of New Guinea: Papua Barat (Bird's Head, Geelvink Bay, Jayapura); northern Papua New Guinea (West Sepik Prov.).
3 Some specimens of H. inflexa from Japen I. resemble H. parviflora by rather unbranched spike-like inflorescences; H. parviflora has more pronounced pear-shaped flowers and paler, not angular twigs. In most of the specimens of H. inflexa, the male inflorescences are distinctly branched with the lateral branches almost unbranched and spike-like. 2 Horsfieldia inflexa resembles H. moluccana in general shape and texture of the leaves, and the relatively long petioles. It can also be confused with the related species H. angularis and H. basifissa. Horsfieldia moluccana generally has more pear-shaped male buds and differs from H. inflexa in terete or faintly lined twigs and not dotted leaves. Horsfieldia angularis is distinguishable by not dotted leaves, hairy flowers, an androecium with a narrow central crevice and straight anthers. Horsfieldia basifissa has, in contrast, terete or only faintly ridged twigs, and differs further in various characters of the male flower including the androecium. 1 This is the only Horsfieldia in New Guinea with dark dots on the lower leaf surface.