Format: ORAL

Jorge Calvo-Yuste1, 2, M. Montserrat Martnez-Ortega1, 2, Teresa Malvar-Ferreras2; Juan Viruel3 & Pablo Tejero4, 5,

1 Área de Botánica, Universidad de Salamanca, Spain; 2 Herbario y Biobanco de ADN vegetal, Universidad de Salamanca, Spain; 3 Royal Botanic Gardens, Kew, Richmond, UK; 4 Instituto Pirenaico de Ecología (IPE-CSIC), Jaca, Spain; 5 Aranzadi Society of Sciences, Donostia-San Sebastián, Spain.

Cliffs are fragmented environments that host a great diversity of specialist plant taxa, often with narrow distribution areas. Despite being harsh environments for plant life, they played a key role as refugia during the climatic and topographic changes of the Cenozoic, representing nowadays reservoirs of relict biodiversity. Besides, the challenging conditions that plants have to face in these habitats seem to have promoted radiative diversification of some rock specialist lineages. Here, we focus on the paradigmatic case of Petrocoptis A.Braun ex Endl. (Caryophyllaceae), a genus of chasmophytic plants endemic to the limestone cliffs and overhangs of the northern Iberian Peninsula. In order to try to shed light on the evolutionary processes that may have contributed to shape vascular plant life on vertical rocks, we reconstructed the phylogenetic relationships within the genus following both a target enrichment sequencing and genome skimming approach (i.e., Hyb-Seq). In addition, we measured a set of morphological traits, particularly those referred to seed morphology. The data obtained allowed reconstruction of the whole plastid genome and revealed an evolutionary history that shows strong geographic signal across the genus, which evidences very limited seed dispersal, strong isolation and vicariance, even at population level. The nuclear phylogeny does not generally show such a strong geographic pattern, probably due to higher pollen flow, and supported most of the previously accepted taxa. The integration of morphological data further contributes to support the idea that high phenotypic plasticity may be a key strategy for long term survival of lineages. Finally, we discuss the potential role of this each valley apart evolutionary strategy as responsible for the great richness of (narrow) endemics that mid-altitude rocky habitats harbour in the Iberian Peninsula and Mediterranean region, and its implications for plant conservation.