The ornamentally important genus Adonis L. (Ranunculaceae) consists of about
30 species. In Iran, 8 species are recognized. The new classification system
recognizes two subgenera, six sections, and six series for Adonis. The
species differentiation within the genus is controversial due to
morphological overlaps in different species and extensive morphological
variation. Therefore, the aims of present study were: 1- Species
delimitation within the Sect. Adonis based on morphological and molecular
evidences and, 2- Studying the species relationship based on molecular
phylogeny. Multivariate analyses of morphological and molecular (ITS and
ISSR) data differentiated the Adonis species. PCA biplot analysis of
morphological characters revealed morphological characters such as leaf
arrangement; leaf length, flower diameter, petal length and width, calyx
length, and pedicel length are of taxonomic implication in Adonis. Bayesian
tree of ITS sequences revealed that the sect. Adonis is differentiated from
the sect. Adonanthe. Based on ITS data, A. microcarpa showed close affinity
to A. scrobiculata, while A. aestivalis, A. icrocarpa and A.dentata were
close to each other.