Herbs erect and shrubby (probably), most parts with reddish brown hairs, dioecious. Stems 3-4 mm thick, furrowed when dry, glabrescent. Petiole 5-13 mm, densely pubescent, prophyll to 3 cm, glabrous; leaf blade elliptic-lanceolate to obovate, strongly asymmetric, 14-25 × 6-11 cm, thinly papery, without evident glands, abaxially densely brown pubescent, nearly tomentose on veins, adaxially sparsely minutely scabrid, base strongly obliquely cordate, basal lobes overlapping, bilateral difference to 3 mm, apex long acuminate; veins 8-10, 3 on narrower side, up to 7 on wider side, apical pair arising 2-6 cm above base, alternate, nearly reaching leaf apex, next pair often also above base; reticulate veins lax, transversely oblong, slightly raised abaxially. Male spikes not seen. Female spikes leaf-opposed, 27-30 cm × 6-7 mm in fruit; peduncle 4-4.5 cm, glabrous; rachis pubescent; bracts orbicular, peltate, margin pale when dried, 1.5-1.7 mm in diam. Ovary ± cylindric; stigmas 3 or 4, reflexed, very short and inconspicuous. Drupes densely packed, prismatic-cylindric, ca. 2 × 1.5 mm. Fr. Apr.

Plants of this species were named as Piper spirei in FRPS, but examination of the type of that name has shown that it belongs to P. boehmeriifolium.

* Wet places within forests. S Yunnan (Xishuangbanna Daizu Zizhizhou)