Rhodiola atuntsuensis (Praeger) Fu

Rhodiola atuntsuensis shows a wide range of variation, especially in leaf shape and flower number. Several allied species are better regarded as extreme variants of this species. The species is functionally dioecious, but the male flowers have large pistils and appear bisexual.

Caudex few branched, erect, 3-5 × 0.5-1.2 cm; persistent old flowering stems present or absent. Caudex leaves scalelike, triangular to triangular-suborbicular, apex acute to acuminate. Flowering stems few to numerous, simple, erect, 2-9 cm. Stem leaves alternate, sessile or shortly petiolate; leaf blade broadly oblong-lanceolate, obovate-lanceolate, oblong-ovate, or subovate, (5-)6-12 × 2.5-4 mm, base connate, margin entire but sometimes undulate, apex rounded, obtuse, or acuminate. Inflorescences subumbellate or corymbiform. Flowers bisexual or unisexual, 5-merous, or 4-merous in male plants. Sepals linear, lanceolate, or broadly oblong, 1.5-6.5 mm, base ca. 1 mm wide and connate for ca. 1 mm, apex obtuse. Petals suberect, yellow or purple at base and yellow toward apex, oblong-linear, oblong, oblong-lanceolate, or obovate, 2.5-4.5 × 1-0.6-2.5 mm, apex obtuse and mucronate. Stamens 8 or 10, subequaling petals; antepetalous ones inserted ca. 0.5 mm from petal base. Nectar scales subelliptic to obliquely quadrangular, apex ± emarginate. Carpels suberect or erect, 2.5-4 mm. Seeds subovoid-oblong, smooth, winged at both ends. Fl. and fr. Aug.

W Sichuan (Dawu Xian, Kangding Xian), Xizang, NW Yunnan [Myanmar].

Forests, glacial valleys, granitic rocks, gravelly or limestone areas; 3100-5000 m.

Sedum atuntsuense Praeger, Notes Roy. Bot. Gard. Edinburgh 13: 71. 1921; Chamaerhodiola atuntsuensis (Praeger) Nakai; Rhodiola aporontica (Fröderström) S. H. Fu; R. brevipetiolata (Fröderström) S. H. Fu; R. concinna (Praeger) S. H. Fu; R. nobilis (Franchet) S. H. Fu subsp. atuntsuensis (Praeger) H. Ohba; R. venusta (Praeger) S. H. Fu; Sedum aporonticum Fröderström; S. brevipetiolatum Fröderström; S. concinnum Praeger; S. venustum Praeger.