Perennial herbs. Tap roots columnar; lateral roots tuberous or fusiform, sometimes tandem-fusiform. Stems usually green or green but pale purple in the lower part, sparsely to densely hirsute, 30-70 cm tall, with 4-9 green or greenish yellow scales at the base. Petioles and petiolules always hirsute; lower leaves biternate, with 9, rarely 8, leaflets, usually one or several leaflets segmented and thus leaflets/leaf segments 9-15, very rarely up to 25 in number, ovate, oblong or elliptic, cuneate to rounded at the base, nearly rounded to acute at the apex, 4.5—12 cm long, 1.5-7 cm wide, glabrous above, mostly densely, less frequently sparsely, villose beneath. Flowers solitary and terminal; involucrate bracts 1-3 in number, leaf-like; sepals 3-4 in number, with one caudate and the rest rounded at the apex, nearly orbicular, 2-4 cm long, 1.5-3.5 cm wide, green but purple at the periphery or entirely purple, densely villose on the abaxial side; petals 6-8 in number, dark purple, oblong or obovate, entire or 2—lobed at the apex, 4.5-6 cm long, 3-4.5 cm wide; filaments purple; anthers purple; disk 1-1.5 mm high, waved, tomentose; carpels 1-3, but mostly 2 in number, columnar-ellipsoid, 1.4-2.2 cm long, 0.5-0.7 cm in diameter, yellowish tomentose, hairs 2 mm long; stigmas sessile, red, c. 2 mm wide.
Chromosome number: n=20 (tetraploid).
Growing at the edges and in openings of Abies forests, or in sparse Abies forests, on limestones, at an altitude of 1,100—1,500 m. Found only in the mountains Parnassos and Elikonas (Helicon) of Greece.
The most remarkable characters of Paeonia parnassica are its very dark purple petals and purple anthers, which distinguish it from P. arietina. It has fewer leaflets/leaf segments (9—15, rarely up to 25) than P. arietina (11-25, rarely up to 32).
- Hong, De-Yuan. “Peonies of the World. Taxonomy and phytogeography.” Kew: Royal Botanic Gardens, 2010, p. 227-228.