Perennials. Tap roots carrot-shaped, up to 3 cm in diameter, lateral roots thin and basipetally attenuate. Stems usually purple, less frequently green, glabrous, 30—80 cm tall. Lower leaves biternate, usually most or nearly all leaﬂets segmented; leaﬂets/leaf segments 11—32, but mostly 15—21 in number, elliptic or ovate—lanceolate, rarely obovate, 4-10 (15) cm long, 1.5—5(6.5) cm wide, cuneate at the base, acute or short—acuminate at the apex, glabrous on both sides, very occasionally sparsely puberulous beneath. Flowers solitary and terminal; involucrate bracts 2 or 1 in number, leaf-like, or very rarely absent; sepals usually 3, rarely 4 in number, mostly rounded at the apex, up to 3 cm long, 2.6 cm wide, green but purple at the periphery, glabrous, very occasionally puberulous on the abaxial side; petals 6—7 in number, pink-red, 5—6 cm long, 3—4 cm wide; ﬁlaments yellow or purple; anthers yellow; disk waved, 2 mm high, glabrous or tomentose; carpels mostly 2 or 3, less frequently 1 or 4, very occasionally 5 in number, tomentose, hairs 2 mm long, rust-brown; stigmas sessile, red, 2.5 mm wide. Follicles 2.5—4 cm long, 1.3-1.6 cm in diameter. Seeds oblong, black, 7-8 mm long, 5—6 mm wide.
Chromosome number: 2n = 10 (diploid)
Growing in shrubs, oak or pine forests, in limestone soils at altitudes from 300 to 1,830 m. Conﬁned to the Iberian Peninsula (Spain and Portugal). (We saw two collections from Morocco on a sheet in the Botanical Museum, University of Lund, Sweden. One is from Mt (Djebel) Hassen, 1910—1911, M. Gandoger s.n. and the other from Mt Onezzan, 1910—1911, M. Gandoger s.n. According to Dr G. Dahlgren (personal communication), the field records of Gandoger’s collections were often mixed up.)
Paeonia broteri is characterised by plants glabrous throughout except carpels, leaﬂets or segments relatively narrow with a relatively high number. The species is closely related to P. clusii, and their relationship is discussed under that species. Paeonia broteri also resembles P. coriacea and P. mascula to some extent, but differs from the former in having tomentose carpels and narrower leaﬂets/leaf segments (1.5—5—(6.5) rather than 2—8 cm wide), and from the latter in having more leaﬂets or segments (11-32 rather than 10—18—(21)), which are smaller (4—10—(15) x 1.5—5—(6.5) cm rather than 4.5—18 x 3-9 cm) and nearly always glabrous, and shorter hairs on carpels (2 mm rather than 3 mm long). Furthermore, P. broteri is a diploid (2n = 10), whereas P. coriacea and P. mascula are tetraploid (2n = 20). We found P. broteri and P. coriacea coexisting in the Alfacar Mountains, NE of Granada, but they appeared distinct.
- Hong, De-Yuan. “Peonies of the World. Taxonomy and phytogeography.” Kew: Royal Botanic Gardens, 2010, p. 160.