Comparative anatomical studies in relation to taxonomy of Sedum s.l. (Crassulaceae) in Iran

This study aimed to characterize the stem, peduncle, and leaf anatomy of 22 species of Sedum senso lato distributed in Iran. The results showed that the presence of tanniniferous storage cells in stems and leaves, distinct xylem vessels in stems, and the shape of peduncle cross sections, were taxonomically informative evidence, and isolated Phedimus from the other studied taxa of Sedum s.l., whereas hairy leaves and peduncles containing starch storage cells were identified as Prometheum and Hylotelephium respectively. In addition, the current anatomical evidence confirmed the alliance of 2 sections of Sedum and Epeteium within Sedum sensu stricto. The result of numerical analysis (including 31 qualitative and quantitative anatomical characters) supported complete separation of the fourallied genera and revealed significant influence of anatomical traitsin taxonomy of Sedum s.l.