Sibbaldia olgae Juz. & Ovczinn
Tomentose to almost glabrous prostrate herbs. Leaves trifoliolate, pinnate or palmate, petioles 0.7-8.5 cm long, tomentose, hairs stiff, usually appressed grey, stipules 5-15 x 2-5 mm, membranaceous. Leaflets 3, 12-30 x 6-17 mm, sessile or petiolulate, not articulated at base, the petiolules to 3.5 mm long, blades obovate or obovate-cuneate, apex tru ncate with 3-5(-8) glandular tipped teeth, the blades densely tomentose to glabrescent or glabrous on both surfaces. Inflorescence comprised of 5-11 flowers in dense, ± umbell-l ike, bracteate cymes, pedicles 1.2-2.5 mm long, glabrescent to densely tomentose, bract 4-10 x 1-2.5 mm, lanceolate, acute, 1.5-6 x 0.7-3 mm, bracteoles 0.3-1.5 x 0.6-1 mm, oblong-lanceolate, cup-shaped. Flowers perfect, 5-merous, epicalyx lobes 5, 1.5-2.2 x 0.2-0.5 mm, linear, acute. Sepals 5, 1.7-2.5 x 0.7-12 mm, oblong-lanceolate to ovate deltoid, apices mostly glandular. Petals 5, yellow, 0.6-2.2 x 0.5-1 mm, elliptical to obovate or obovate-spathulate, obtuse, Stamens 5, antisepalous, filaments linear, 0.2-8 mm long, the anthers 0.4-.0.5 mm long and broad, c. elliptical, disc 1.5-2 mm across, sometimes lobed, surrounding the hairy receptacle. Carpels 5 or 6, ovary ± reniform, 0.2-0.5 x c.0.4 mm, styles lateral, glabrous, 0.5-0.9 mm long, stigma ca. 0.05 mm across. Achenes 1-1.5 x ca. 1 mm, glabrous, mostly glossy, smooth dark to light brown.
Fl. Per.: July-August.
Lectotype: ‘Habitat in Alpibus Lapponiae, Helvetiae, Scothiae’ RCN: 2261, Amman s.n., Herb. Linn. No. 401.1 (LINN) (Jarvis, Order out of Chaos. 846. 2007).
A-7 Gangalwat Gol, Kafristan, s.w. of Chitral, Stainton 2722 (A,BM): A-8 Karakorum, Gharesa Glacier Base Camp. 13 miles east of Nagar, Polunin 6154 (B, BM).
Distribution: Widely distributed in Asia, Europe and North America.
On wet quartzite rocks, granitic rocks, and in moist places on calcareous rocks, generally on gravelly soil and rock slides, 300-3500 m.
Sibbaldia procumbens has a wide geographical distribution and spans the greatest latitude of any species in the genus Sibbaldia but populations are discontinuous between Europe, America and Southeast Asia. Correspondingly, the species consists of a series of relatively pronounced forms, many of which have been described as distinct taxa. However, plants similar to a form characteristic of one area frequently occur in a population from another part of the range. Hence it is not possible to split it into more taxa.