Tree c. 30 m. Leaves chartaceous, oblong-lanceolate, ± parallel-sided, 50 by 14 cm, base broadly rounded to subcordate, apex acute-acuminate; Inflorescences (female) with woolly hairs 0.3-0.5 mm long, about 3 times branched, 4-5 by 3.5 cm, rather many-flowered; Fruits not seen.
Asia-Tropical: Borneo present (Sarawak present), Sibu District, 3rd Div., Sg. Tutus, Loba Kabang P.F present
Malesia: Borneo (Sarawak: Sibu District, 3rd Div., Sg. Tutus, Loba Kabang P.F.); known only from the type.
The only specimen known is reminiscent of some other stout-leaved Horsfieldias, such as H. sylvestris from SE Malesia, and to a lesser extent H. pulcherrima (Sumatra), H. splendida (Borneo), and H. superba (Peninsular Malaysia, Sumatra), but H. sessilifolia is distinguishable in almost sessile leaves and the densely short-pubescent lower leaf surface. Horsfieldia sylvestris is generally less stout; and has similarly subsessile (but narrower) leaves and 2-lobed perianths. The other stout-leaved species mentioned here all have distinctly petioled leaves.