Format: ORAL

Bocanegra-Gonzlez K.T. Aranguren Y. Fernndez-Mndez F.

1. The University of Edinburgh 2. Royal Botanic Garden Edinburgh 3. Research Group on Biodiversity and Dynamics of Tropical Ecosystems (GIBDET), University of Tolima 4. University of Tolima 5. University Simón Bolívar

An endemic species occurs naturally, exclusively, and is highly adapted to a specific geographic area. If this area is very small, the species is termed as local endemic and generally consists of small or a single population. The genus Magnolia is an interesting study model of local endemism since out of the 39 species recorded for Colombia, 80% are endemic and restricted to less than 100 km2. The species of the genus are also hermaphroditic, and both entomophily and self-pollination are reported as their main reproductive syndromes. Here we study Magnolia calimaensis (Lozano) Goavaerts, an endemic tree species of the Bajo Calima region on the Pacific coast of Colombia, which is critically endangered with fewer than 100 individuals in the wild. To understand the origin of local endemism in M. calimaensis, 38 individuals were sampled from Bajo Calima and Baha Mlaga localities. Microsatellite marker analysis revealed low genetic diversity and high inbreeding coefficients for both populations (He: 0.24 / F: 0.53 for Bajo Calima, and He: 0.29 / F: 0.29 for Baha Mlaga). Significant genetic differentiation between locations suggests dissimilar population conditions. Results imply that the species gregarious distribution and local endemism may be linked to reproductive biology, like geitonogamy, rather than landscape composition. Urgent genetic restoration strategies are needed to preserve M. calimaensis populations, highlighting the importance of further reproductive biology studies.