Format: ORAL

Joana Cursach1, Miquel Cap2, Theodora Petanidou3 and Amparo Lzaro4,5Joana Cursach1, Miquel Cap2, Theodora Petanidou3, Amparo Lzaro4,5

1 Research Group on Plant Biology under Mediterranean Conditions, Department of Biology, University of Balearic Islands, Palma, Spain 2 Plant & Animal Ecology Lab. Centro para la Conservación de la Biodiversidad y el Desarrollo Sostenible, Departamento de Sistemas y Recursos Naturales, Universidad Politécnica de Madrid, Madrid, Spain 3 Laboratory of Biogeography & Ecology, University of the Aegean, Mitilene, Greece 4 Global Change Research Group, Mediterranean Institute for Advanced Studies (UIB-CSIC), Esporles, Spain 5 Area of Ecology, Department of Biology, University of Balearic Islands, Palma, Spain

The threat categories proposed by IUCN are mostly based on trends in population sizes and geographical range estimates. However, other factors could also be predictors of plant vulnerability, such as those related to the architectural complexity of flowers (e.g. floral shape and symmetry), or plant reproduction (e.g. flowering duration, life form, capability of asexual reproduction). Here, we analysed plant traits that could be potential predictors of vulnerability focusing on the endemic flora of the Balearic Islands, a hotspot of biodiversity and endemicity within the Mediterranean Basin. For this, we compiled the list of entomophilous plant species endemic to the Balearic Islands, categorized their vulnerability according to the regional Red Data Book, and gathered bibliographic data about both intrinsic and extrinsic factors that could affect plant vulnerability. We selected 10 intrinsic factors (floral shape, floral tube length, floral symmetry, corolla segmentation, floral size, floral colour, flowering season, flowering duration, life form and the capability of sexual reproduction) and one extrinsic factor (main habitat). The endemic entomophilous flora of the Balearic Islands comprises 156 taxa, 57 of which (37%) are threatened (EW, CR, EN and VU). We used Generalized Linear Models to test the potential effects of both intrinsic and extrinsic factors on plant vulnerability using a binomial response variable with two categories: threatened (EW, CR, EN, VU) and not threatened (NT, LC), and obtained optimal models based on the Akaike Information Criterion to select the best predictors for plant vulnerability. Our results showed that flowering duration and habitat were main predictors of vulnerability in the endemic flora of the Balearic Islands. Plants with short flowering duration, and freshwater, littoral and mountain plants were those more threatened. This study emphasizes the importance of studying other useful traits as indicators of species extinction risk in order to enhance plant conservation.