Format: ORAL

Caadas, E.M.1, Calderisi, G.2, Lorite, J.1, Cogoni, D.2, Fenu, G.2

1 Department of Botany, University of Granada, Granada, Spain 2 Department of Life and Environmental Sciences

Currently, over 28% of species are at risk of extinction, which could rise to 50% by 2100 since the rate of extinction has been particularly dramatic for the last 50 years. Conifers stand out as a highly endangered group, with a percentage of threatened species of c. 34%. Reversing the situation is crucial since coniferous species, which are mostly trees, constitute key pieces for more than 39% of the worlds forests and for the provision of ecosystem services globally. Deforestation and other man-made hazards, including climate change, threaten conifers which, like other gymnosperms, are also doomed to extinction due to natural causes. In this context, we explore intrinsic or natural traits (both biological and ecological) leading conifers to extinction in order to support decision-making on biodiversity conservation. Furthermore, we delved into the largest conifer family, Pinaceae. For this, we downloaded from the IUCN Red List database all the 610 species from the Pinopsida Class, assigning the global Red List category. For each species we also compiled traits related to altitude, adult plant size, and seed size. Moreover, for the Pinaceae family (225 species), we collected traits about leaves, seed cones, pollen cones, and seed wing, among others. Then we assessed the relationship between extinction risk (with values ranging between 1 (LC) and 5 (CR)) and traits, finding that the most threatened conifers are smaller in size, have smaller seeds, and inhabit a narrow altitudinal range at mid-mountain. Pinaceae showed similar trends, but the most endangered species had heavier seeds and smaller leaves in this case. Our results could guide conservation efforts for these plants custodians of an ancient and long evolutionary history, since species with certain identified traits could be more vulnerable to moving to a higher threat category if no action is taken.