Format: ORAL

Francisco LARA1,2, Juan LARRAN3, Ricardo GARILLETI4 Isabel DRAPER1,2

1 Departamento de Biología, Universidad Autónoma de Madrid, Spain. 2 Centro de Investigación en Biodiversidad y Cambio Global, Universidad Autónoma de Madrid, Spain. 3 Centro de Investigación en Recursos Naturales y Sustentabilidad (CIRENYS), Santiago, RM, Chile 4 Departamento de Botánica y Geología, Universidad de Valencia, Spain.

The five global regions with Mediterranean climates harbor high and unique biodiversity, hence all being part of recognized hotspots. A climate characterized by a prolonged period of drought coinciding with the hottest time of the year may not seem, at first glance, favorable for bryophytes. However, several groups of mosses and liverworts are widely diversified in this environment. The representation of Orthotrichaceae in the different Mediterranean floristic regions is highly unequal, both in terms of the genera present, and in the overall specific diversity. The Mediterranean Basin and the California Floristic Province boast a notable diversity of species distributed among few genera, all belonging to the subfamily Orthotrichoideae. Conversely, in the Cape Floristic Province and Southwest Australia, there are relatively few species, but there is a significative presence of Macromitrioideae genera. In contrast to this, in Central Chile the diversity reported so far is very low, both in number of genera and species, with all taxa belonging to Orthotrichoideae. But, to what extent is this diversity scenery realistic for the southern hemisphere Mediterranean areas? Our studies in Central Chile indicate that there is indeed a considerable hidden diversity of Orthotrichaceae there. Specifically, our results unveil that there is a high number of previously unknown species belonging to the genera Orthotrichum and Lewinskya. Most are species restricted to the Chilean Mediterranean biome. However, two particularly diverse environments, sharing few species among them, can be distinguished: the fog oases of the coastal hills and the high elevation zones of the inland Mediterranean mountains. We provide data on the adaptive morphological characteristics of the new species, their distribution patterns, and their phylogenetic relationships, considering a broad framework that integrates species from other South American areas and the remaining Mediterranean regions worldwide.