In defence of the entity of Macaronesia as a biogeographical region

• Published in: Biological Reviews
• Main Authors: Fernández-Palacios, José María, Otto, Rüdiger, Capelo, Jorge, Caujapé-Castells, Juli, de Nascimento, Lea, Duarte, Maria Cristina, Elias, Rui, García-Verdugo, Carlos, Menezes de Sequeira, Miguel, Médail, Frédéric, Naranjo-Cigala, Agustín, Patiño, Jairo, Price, Jonathan, Romeiras, Maria, Sánchez-Pinto, Lázaro, Whittaker, Robert
• Other Authors: Institut méditerranéen de biodiversité et d'écologie marine et continentale (IMBE), Avignon Université (AU)-Aix Marseille Université (AMU)-Institut de recherche pour le développement IRD : UMR237-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2024
• Subjects: [SDE]Environmental Sciences; Webb; North Atlantic
• Online Access: https://amu.hal.science/hal-04617931; https://doi.org/10.1111/brv.13112

International audience ABSTRACT Since its coinage ca . 1850 AD by Philip Barker Webb, the biogeographical region of Macaronesia, consisting of the North Atlantic volcanic archipelagos of the Azores, Madeira with the tiny Selvagens, the Canaries and Cabo Verde, and for some authors different continental coastal strips, has been under dispute. Herein, after a brief introduction on the terminology and purpose of regionalism, we recover the origins of the Macaronesia name, concept and geographical adscription, as well as its biogeographical implications and how different authors have positioned themselves, using distinct terrestrial or marine floristic and/or faunistic taxa distributions and relationships for accepting or rejecting the existence of this biogeographical region. Four main issues related to Macaronesia are thoroughly discussed: ( i ) its independence from the Mediterranean phytogeographical region; ( ii ) discrepancies according to different taxa analysed; ( iii ) its geographical limits and the role of the continental enclave(s), and, ( iv ) the validity of the phytogeographical region level. We conclude that Macaronesia has its own identity and a sound phytogeographical foundation, and that this is mainly based on three different floristic components that are shared by the Macaronesian core (Madeira and the Canaries) and the outermost archipelagos (Azores and Cabo Verde). These floristic components are: ( i ) the Palaeotropical‐Tethyan Geoflora, formerly much more widely distributed in Europe and North Africa and currently restricted to the three northern archipelagos (the Azores, Madeira and the Canaries); ( ii ) the African Rand Flora, still extant in the coastal margins of Africa and Arabia, and present in the southern archipelagos (Madeira, the Canaries and Cabo Verde), and ( iii ) the Macaronesian neoendemic floristic component, represented in all the archipelagos, a result of allopatric diversification promoted by isolation of Mediterranean ancestors that manage to colonize Central ...