Perennials. Tap roots up to 1 m long, thickened, carrot—shaped, attenuate downwards, up to 2 cm in diameter, lateral roots also carrot-shaped, neither tuberous nor fusiform. Lower leaves biternate; leaflets often decurrent, finely segmented; lower leaves with leaflets 9 and segments 70—100 in number; segments 2—13 cm long, 0.8—3.2 cm wide, with bristles along veins above, glabrous beneath. Flowers solitary or 2-4 on a stem, often only the terminal one fully developed and blooming; involucrate bracts 1—3 in number, leaf—like; sepals 3-5 in number, mostly caudate at the apex, rarely 1 or very occasionally 2 non—caudate, hispidulous only near the top on the adaxial surface, glabrous, very rarely hispidulous on the abaxial surface; petals rose, pale red or red, but rarely white in subsp. veitchii, 6—9 in number, obovate, entire or incised at the apex, 4—5.5 cm long, 3-4 cm wide; disk waved, c. 1.5 min high; carpels mostly 3 to 5 in number, densely tomentose, rarely sparsely hairy or glabrous; ovules 12—16 in number per carpel; styles absent or less than 0.5 mm long; stigmas red, 2 mm wide. Follicles columnar, 1.5-2.8 cm long, 1—1.2 cm wide. Seeds ovoid or ovoid-spherical, black, 6—7 mm long, 4.5-5 mm wide.
Chromosome number: 2n = 10 (see the subspecies for detail).
Preferring relatively moist habitats, growing in forests, on the edges of forests, or rarely in bushes or meadows. It is found from lowlands to an altitude of 3,870 m. A few collections recorded limestones, granites and sandstones as the media in which this species grows. Widely distributed from China to the Kola Peninsula of Russia via Siberia and Central Asia.
Pallas’s (1788) illustration has only one name, Paeonia sibirica, and apparently he used this illustration also for P. laciniata, because one sees “Paeonia laciniata” on p. 93. Paeonia laciniata was described in detail by Pallas, but no description was given for P. sibirica by him.
Paeonia anomala had been confused with P. intermedia and P. hybrida long before the work of Hong and Pan (2004), who reviewed the taxonomy of this complex and discussed its relationships in detail on the basis of field observations and examination of the types of these three taxa and a large quantity of specimens. Since the work of Sims (1815), all authors described the root of P. anomala as tuberous (or fusiform), e.g. Anderson (1818), Schipczinsky (1937), Gamaulova (1961), or gave no description of its roots, e.g. de Candolle (1818), Lynch (1890) and Stern (1946). Actually, P. hybrida is a synonym of P. tenuifolia, as in Anderson’s treatment (1818). According to our observations in the Altai, the populations that had the majority of sepals caudate at the apex always had carrot—shaped roots, whereas those with more sepals rounded (non-caudate) at the apex always had tuberous roots. The examination of specimens from Siberia and Mongolia shows that they consistently had the majority of sepals caudate at the apex and carrot-shaped roots. The type of P. anomala L. is from Siberia, and the two sepals visible on the sheet are both caudate at the apex. Most specimens examined from western and southern parts of the Altai westward to Uzbekistan had tuberous roots, if roots were collected, and most sepals were non-caudate. The type of P. intermedia C. A. Mey., which was collected from the Altai, has tuberous roots. It is clear that P. anomala has carrot-shaped roots, which are correlated with caudate sepals, whereas P. intermedia has tuberous roots, which are correlated with non-caudate sepals.
Saunders and Stebbins (1938) made crosses between P. anomala and P. veitchii, P. anomala and P. beresowskii, P. anomala and P. woodwardii, P. veitchii and P. beresowskii, P. veitchii and P. woodwardii, and P. beresowskii and P. woodwardii. All of these species pairs were easily crossed and the hybrids were fertile, similar to crosses between individuals of the same subspecies. This is consistent with the conclusion we reached on the basis of external morphology: these four taxa fall within the same species.
Paeonia anomala has two allopatric subspecies, with the typical subspecies distributed northwest of the Gobi, whereas the subspecies veitchii is in China southeast of the Gobi
Key to subspecies of Paeonia anomala
- Hong, De-Yuan. “Peonies of the World. Taxonomy and phytogeography.” Kew: Royal Botanic Gardens, 2010, pp. 125-127.