J Syst Evol

• Research Article •    

Untangling the origin and diversification of the Carthamus–Carduncellus complex (Cardueae, Compositae) in the Mediterranean basin

Roser Vilatersana1*, Juan Antonio Calleja2, Sonia Herrando‐Moraira1, Núria Garcia‐Jacas1†, and Alfonso Susanna1   

  1. 1 Botanic Institute of Barcelona (IBB, CSIC‐Ajuntament de Barcelona) Pg. del Migdia s.n., Barcelona 08038, Spain;
    2 Department of Biology (Botany), Faculty of Sciences, Research Centre on Biodiversity and Global Change (CIBC‐UAM), Universidad Autónoma de Madrid, Madrid 28049, Spain
    Our coauthor Núria Garcia‐Jacas passed away in April 2023, when this paper was already finished. Rest in peace.
    *Author for correspondence. E‐mail: vilatersana@ibb.csic.es
  • Received:2023-10-04 Accepted:2024-01-11 Online:2024-02-24

Abstract: Understanding the richness and diversification processes in the Mediterranean basin requires both knowledge of the current environmental complexity and paleogeographic and paleoclimate events and information from studies that introduce the temporal dimension. The Carthamus–Carduncellus complex (Cardueae, Compositae) constitutes a good case study to investigate the biogeographic history of this region because it evolved throughout the basin. We performed molecular dating, ancestral area estimation, and diversification analyses based on previous phylogenetic studies of a nearly complete taxon sampling of the complex. The main aims were to determine the role of tectonic and climatic events in the disjunction of the complex and the expansion route of the two main lineages, Carduncellus s.l. and Carthamus. Our results suggest that the main lineages in the complex originated during the Miocene. Later, all main paleogeographic and paleoclimatic events during the Neogene and Pleistocene in the Mediterranean basin had an important imprint on the evolutionary history of the complex. The Messinian Salinity Crisis facilitated the dispersion of the genus Carduncellus from North Africa to the Iberian Peninsula and the split of the genera Phonus and Femeniasia from the Carduncellus lineage. The onset of the Mediterranean climate in the Pliocene together with some orogenic processes could be the main causes of the diversification of the genus Carduncellus. In contrast, Pleistocene glaciations played a key role in the species diversification of Carthamus. In addition, we emphasize the problems derived from secondary dating and the existing differences between two previous dating analyses of the tribe Cardueae.

Key words: biogeographic history, diversification analyses, Mediterranean climate, Messinian salinity crisis, molecular dating, Pleistocene glaciations