Format: ORAL

Sara Martn-Hernanz1,2, Abelardo Aparicio2, Juan Viruel3, Bjrn Widn4, Polina Volkova5, Mohamed Djamel Miara6, Encarnacin Rubio2, Rafael G. Albaladejo2

1 Universidad Complutense de Madrid, Madrid, Spain 2 Universidad de Sevilla, Sevilla, Spain 3 Royal Botanic Gardens, Kew, Richmond, United Kingdom 4 Lund University, Lund, Sweden 5 Papanin Institute for Biology of Inland Waters RAS, Borok, Russia 6 Ibn Khaldoun University of Tiaret, Tiaret, Algeria

The study of complex plant groups demands a comprehensive approach, encompassing macroevolutionary and microevolutionary scales. By integrating diverse data sources, we aim to offer a thorough perspective that aids in resolving taxonomic and systematic questions. Next Generation Sequencing technologies present a significant opportunity for unraveling the evolutionary processes within these challenging groups. Among these groups, the genus Helianthemum stands out as the most extensive genus within the Cistaceae family, boasting over 140 species and subspecies, included in 3 subgenera and 10 sections. Its distribution range extends from Macaronesia to Central Asia, covering North Africa and central Europe. Notably, Helianthemum exhibits one of the highest diversification rates in the Mediterranean Basin, attributed to three evolutionary radiations since the Pliocene. These radiations align with the three major sections: Eriocarpum, Helianthemum, and Pseudocistus, resulting in a complex taxonomy and nomenclature with poorly defined taxonomic boundaries. In our research, we employ an integrative approach that combine genomic techniques (GBS, target capture), ecological analyses (soil, climate), and morphological assessments (vegetative, floral, and karyological traits) at both macroevolutionary and microevolutionary levels. Our goal is to unravel the processes contributing to this taxonomic complexity and establish practical boundaries across all taxonomic ranks, from subgenera and sections to species and subspecies. Macroevolutionary findings indicate that higher taxonomic ranks (subgenera and sections) are generally well-defined in terms of phylogenetic, ecological, and morphological criteria. On the microevolutionary front, our investigation of polymorphic species within sect. Pseudocistus (H. marifolium, H. cinereum, and H. oelandicum) reveals compelling evidence of some introgression between them and the parallel evolution of characters previously used to define subspecies. This emphasizes the need for a synthetic taxonomic treatment with stable diagnostic characters at the lowest taxonomic levels.