RT Journal Article T1 Are We Witnessing a Speciation Continuum? Evidence From Current and Past Gene Flow in the Genus Oritrophium s.s. (Asteraceae) From the Tropical High Andes A1 Gorospe, Juan Manuel A1 Salomón, Luciana A1 Armijos-Barros, Jorge A1 Kantor, Adam A1 Kolář, Filip A1 Arnelas Seco, Itziar A1 Sklenář, Petr A1 Schmickl, Roswitha AB Determining species boundaries is key for appropriately assessing biodiversity. However, the continuity of the speciation process makes delimiting species a difficult task, especially for recently diverged taxa. Furthermore, past introgression may leave traces that result in reticulate evolutionary patterns, challenging the estimation of species relationships. The fastest-evolving biodiversity hotspot on Earth is the Páramo. Its flora in the tropical high Andes is known for extraordinarily high species richness and endemism. However, the recent origin, fast diversification and complex taxonomy of many genera challenge species delimitation and phylogenetic reconstruction. In this study, we reconstructed phylogenetic relationships and addressed the role of introgression in the diversification of Oritrophium s.s. (Asteraceae) based on phylogenomic data. We combined genomic, phenotypic and ecological data to test species boundaries and compared trajectories across the speciation continuum within the taxonomically complex ‘O. peruvianum group’. We found that historical introgression played an important role in the evolution of Oritrophium s.s., and many of the taxa within the ‘O. peruvianum group’ are at various stages of speciation. These results highlight the importance of testing for introgression to understand the diversification of recently evolved groups. Likewise, they suggest that heterogeneous speciation trajectories associated with geographic isolation and secondary contact, possibly during the Pleistocene, contributed to plant diversity in the tropical high Andes. PB Wiley SN 0962-1083 YR 2025 FD 2025-09 LK https://hdl.handle.net/20.500.14352/125245 UL https://hdl.handle.net/20.500.14352/125245 LA eng NO Gorospe, J. M., L. Salomón, J. Armijos-Barros, et al. 2025. “ Are We Witnessing a Speciation Continuum? Evidence From Current and Past Gene Flow in the Genus Oritrophium s.s. (Asteraceae) From the Tropical High Andes.” Molecular Ecology e70095. https://doi.org/10.1111/mec.70095. NO This study was supported by the Grant Agency of Charles University (GAUK) project No. 96121 to J.M.G.; the Czech Science Foundation GAČR project No. 20-10878S to R.S. and F.K.; the long-term research development project No. RVO 67985939 of the Czech Academy of Sciences; and the Bentham-Moxon Trust project No. BMT25-2018. NO Charles University NO The Czech Science Foundation (GACR) NO Czech Academy of Sciences NO Bentham-Moxon Trust DS Docta Complutense RD 26 feb 2026