Molecular phylogeny and phylogeography reveal recent divergence in the Iberis simplex DC. (Brassicaceae) species complex

Authors: EMRE ÇİLDEN, BARIŞ ÖZÜDOĞRU

Abstract: According to the current taxonomic delimitation, the Mediterranean genus Iberis comprises about 30 species. Among them, the taxonomy and species delimitation of Iberis simplex and its morphologically close relatives (I. attica, I. carica, I. gypsicola, I. halophila, and I. spruneri), described here as the I. simplex species complex, are controversial and several different names are used for the members of this complex. Past phylogenetic studies did not include the members of this complex and here we present the first comprehensive phylogenetic and phylogeographic study based on nuclear ITS and chloroplast trnL-F regions to delimit the boundaries of the species and contribute to the knowledge of Anatolian biogeography. Our analyses clearly showed a monophyletic origin of this complex, polytomic relationships within the clade, and recent divergence of the species of this complex starting from ca. 0.65 million years ago. Finally, a recent population expansion (as a driver of rapid radiation) which is possibly associated with climatic oscillations during the Pleistocene was supported by multiple tests and mismatch distribution analyses.

Keywords: Anatolia, Brassicaceae, phylogeography, Iberis, Iberideae, pleistocene

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