EVIDENCE FOR AN EXTREME BOTTLENECK IN A RARE MEXICAN PINYON: GENETIC DIVERSITY, DISEQUILIBRIUM, AND THE MATING SYSTEM IN PINUS MAXIMARTINEZII.

Maxipiñon (Pinus maximartinezii Rzedowski), which is confined to a single population of approximately 2000 to 2500 mature trees, covers about 400 ha in southern Zacatecas, Mexico. Genetic diversity measured by expected heterozygosity was 0.122, which is moderate for pines.