Format: ORAL

Maxim S. Nuraliev1,2, Anastasia A. Krinitsina1, Nikolay A. Vislobokov1,2, Leonid V. Averyanov3, Khang Sinh Nguyen4,5, Dmitry D. Sokoloff1, Pavel A. Nikitin1Maxim S. Nuraliev1,2, Anastasia A. Krinitsina1, Nikolay A. Vislobokov1,2, Leonid V. Averyanov3, Khang Sinh Nguyen4,5, Dmitry D. Sokoloff1, Pavel A. Nikitin1

1 M.V. Lomonosov Moscow State University, Moscow, Russia 2 Joint Russian-Vietnamese Tropical Scientific and Technological Center, Hanoi, Vietnam 3 Komarov Botanical Institute, St. Petersburg, Russia 4 Institute of Ecology and Biological Resources, Hanoi, Vietnam 5 Graduate University of Science and Technology, Hanoi, Vietnam

Considered recently to contain only a few species, the genus Peliosanthes is currently under active discovery for its taxonomic diversity. Indeed, by the end of the 20th century, it was known to comprise about 15 species, whereas more than 60 formally accepted species are presently known. However, the more taxonomic novelties are published, the less clear the interspecific boundaries become. From a morphological point of view, Peliosanthes can hardly be subdivided into species groups. In the virtual absence of molecular phylogenetic data, this makes the ideas of species proximity and their discrimination from each other highly subjective and often ambiguous. We used high-throughput sequencing approaches to obtain sequences of the entire plastid genomes of 20 specimens representing 18 species of Peliosanthes. Our results indicate that plastome data allow a well-resolved phylogenetic reconstruction of the genus. In some cases, the reconstruction was in congruence with the morphological similarity between species. For example, P. triandra and P. weberi, representing the earlier recognized genus Neolourya, formed a clade. In other cases, in contrast, the phylogenetic pattern obtained has never been predicted. In particular, our results support the distinctness of P. graminea, which was considered to be very close to the widespread and variable P. teta but appeared to be distantly related to the latter. We show homoplastic evolution of several structural traits, including the inflorescence type (raceme vs. thyrse), the absence or presence of a pedicel, the shape of the perianth (rotate vs. more or less cup-shaped), and the shape of the androecial corona (entire vs. lobed). We therefore argue that the significance of these characters for the systematics of Peliosanthes was overestimated, and we refute a number of earlier proposed interspecific relationships. Supported by the Russian Science Foundation, project 24-44-04001.