Paeonia obovata((Hong, De-Yuan. “Peonies of the World. Taxonomy and phytogeography.” Kew: Royal Botanic Gardens, 2010, pp. 137-148.))
Herbs perennial, 30-70 cm tall. Roots thick, carrot—shaped, attenuate toward tip. Caudex usually short, 2—8 cm long. Stems glabrous, with 5—8 pink or yellow-geen scales at the base. Lower leaves spreading or ascending, biternate; leaﬂets 9 in number, entire, very occasionally one of them 2-segmented, obovate, cuneate at the base, rounded or acute at the apex, 5—20 cm long, 4—14 cm wide, glabrous above, glabrous to densely hispid beneath. Flowers solitary, terminal; involucrate bracts 1 or 2 in number, unequal in size, leaf-like, rarely lacking; sepals 2—4, but mostly 3 in number, unequal in size, 1.5-3 cm long, 1.5-2 cm wide, mostly rounded at the apex; petals 4-7 in number, spreading or incurved, white, rose, pink—red, red, purple—red, or rarely white with pinkish base or margins, obovate, 3—5.5 cm long, 1.8—2.8 cm wide; ﬁlaments white, whitish- yellow, or purple below but white above to entirely purple; anthers yellow, orange—red or dark purple; disk yellow, waved, 1—1,5 mm high; carpels mostly 2 or 3, rarely 1, 4 or 5 in number, always glabrous; ovary green; styles 2—5 mm long; stigmas red, 2-3 mm wide. Follicles gradually recurved, ellipsoid, 2—3 cm long. Seeds black, glossy, ovoid-spherical, 6—7 mm long, 5—6 mm in diameter.
Chromosome number: 2n=10 (diploid) and 2n=20 (tetraploid)
In deciduous broad-leaved or mixed broad-leaved and conifer forests, at altitudes from lowlands to 2,800 m.
Widely distributed in E Asia: China (NE, E and central),Japan, the Korea Peninsula and the Far East of Russia
Hong and coworkers have explained clearly why Paeonia japonica and the other taxa were treated in synonymy. Makino (1898) did not designate type for his new variety, var. japonica, so we designated Miyabe and Takeda’s ﬁgure as neotype. Mandl (1921) did not designate type for his new species. A. I. Fritz’s collection matches the protologue very well and the locality is the same as indicated in the protologue. Thus, it might be the specimen, based on which the new species was described.
Paeonia obovata comprises two geographically allopatric subspecies that are keyed out below:
1a. Leaves mostly glabrous or sparsely (occasionally densely) hispid on lower surface; diploid (tetraploids rarely occurring in the Far East of Russia and on Mt Changbai of NE China): subsp. obovata
1b. Leaves usually densely, very occasionally sparsely, hispid on lower surface; tetraploid (the only diploid found in a mixed population in Lushi County, W Henan): subsp. willmottiae
Paeonia obovata subsp. willmottiae
Chromosome number: 2n = 20 (tetraploid).
Growing in broad-leaved deciduous forests mainly on granites, but also on other media such as sandstones and basalts, at altitudes from 800 to 2,800 m. Endemic to China, conﬁned to the mountain area around the Qinling Range: NE Chongqing, W Henan, W Hubei, S Ningxia, Shaanxi, Shanxi, and N Sichuan.
Subspecies willmottiae in Paeonia obovata is characterised by tetraploidy. In contrast to the typical subspecies, the leaves are mostly densely or very densely hirsute or pubescent on the lower surface.