Tree 10-25 m. Leaves membranous or thinly chartaceous, elliptic-oblong to oblong-lanceolate, 10-22 by 3-8 cm, base attenuate, apex acute-acuminate; Inflorescences in male 3 (or 4) times branched, many-flowered, 4-10 by 2.5-6 cm, peduncle 0.2-2 cm long; Fruits 1-20 per infructescence, globose or subglobose, 1.1-1.4 cm diameter, glabrous, drying light to dark brown, with or without coarse, paler coloured lenticels or warts;
Asia-Tropical: New Guinea present, Madang Prov present, Memberamo River area present, N Papua New Guinea present, NE Papua Barat present, Sepik present
Malesia: New Guinea (NE Papua Barat, including Memberamo River area; N Papua New Guinea: Sepik, Madang Prov.).
Apart from H. angularis (see the note under that species) H. basifissa is possibly closely related to H. parviflora, both have glabrous fruits. The globose fruits are often very similar to those of H. pilifera or H. sinclairii; in these two species, however, the fruits are always hairy, at least towards the base. Horsfieldia basifissa has much in common with H. laevigata var. novobritannica, which also has the androecium deeply hollowed inside; the latter has a more hairy perianth. The female flowers of var. novobritannica are not known, but its globose fruits are larger than those of H. basifissa and somewhat hairy at the base. Horsfieldia basifissa is characterized by the subglabrous male flowers with a very deeply cleft perianth, glabrous ovary, and glabrous, globose fruits.