Description from Flora of China
Pegaeophyton bhutanicum H. Hara; Pycnoplinthopsis minor Jafri.
Herbs with slender to stout, apically branched or rarely unbranched caudex to 2 cm in diam. Petiole (0.2-)0.5-3(-5) cm, thin, flattened, not persistent; leaf blade spatulate or oblanceolate, rarely obovate, (0.5-)1-4(-4.5) × 0.4-1.6 cm, thin, glabrous or distal half densely pubescent adaxially with forked or dendritic, often crisped trichomes to 0.6 mm, base subattenuate or cuneate, margin subincised or deeply dentate distally and with (3-)4-8(-12) teeth on each side, apex acute. Fruiting pedicels slender, (0.5-)1-2.5(-4) cm, strongly recurved, much shorter than leaves. Calyx (2.5-)3.5-5 mm, membranous, persisting with fruit, sometimes splitting as fruit develops; lobes deltoid-ovate, 1.5-3.5 × 1-2.5 mm. Petals white, broadly obovate, (0.6-)0.8-1.3 cm × (4-)5.5-8 mm, apex subemarginate; claw obscure, rarely to 1 mm. Filaments slender, median pairs 2-3.5 mm, lateral pair 1.5-2 mm; anthers ovate, ca. 0.4 mm. Fruit linear or oblong, 5-11 × 2-3 mm; valves not veined, papery; style 0.5-1 mm. Seeds oblong, light brown, 1-1.4 × 0.6-8 mm. Fl. May-Jul, fr. Aug-Sep.
The above first record of Pycnoplinthopsis bhutanica from China is based on Ludlow & Sherriff 2735 (BM). Another collection, Ludlow & Sherriff 20312 (BM, TI), was collected in Bhutan near the border with Xizang.
Stony areas at streamsides, wet rocky crevice, open scree, mossy areas below waterfalls, wet rocky ledges; 3000-4500 m. Xizang [Bhutan, India, Nepal, Sikkim].