Format: ORAL

Zohreh Pourghorban1, Yasaman Salmaki1, Maximilian Weigend2

1 Department of Plant Science, University of Tehran, Tehran, Iran 2 Bonn Institute of Organismic Biology, University of Bonn, Bonn, Germany

Cynoglossinae has radiated into a diverse assemblage comprising approximately 200 species, and its evolutionary history has not yet been comprehensively explored. Here, we examine the historical biogeography of Cynoglossinae, employing molecular dating and ancestral area reconstruction to understand how past climate changes and geographical patterns have provoked the diversification of Cynoglossinae. We inferred the evolutionary relationships of Cynoglossinae based on a dataset of 154 taxa, utilizing four plastid markers (trnL-F, rps16, rpl16, and trnKmatK) and one nuclear region (ITS) through PacBio sequencing. The monophyly of Cynoglossinae is strongly confirmed under Bayesian and maximum likelihood approaches. However, the nested position of all segregates confirms the broad concept of Cynoglossum, encompassing all generic segregates. Our biogeographic analysis results suggest that this subtribe likely originated during the middle Miocene in a large area, including East Asia and the Irano-Turanian region. It underwent rapid initial diversification, subsequently and repeatedly expanding its range both westward to Europe (including the Mediterranean region) and Africa, and southward to Australia during the Middle-Miocene to Pleistocene, with a preferential radiation into northern temperate regions. The timing of the diversification of the species-rich clades corresponds with Miocene tectonic events and global climate changes, resulting in increased aridity across Eurasia. Diversification analyses demonstrated a relatively constant diversification rate for all Cynoglossinae. Our results highlight the complexity of processes shaping diversifications in Cynoglossinae, emphasizing a complex interaction among climatic modifications providing opportunities for diversification.