In and out of refugia: historical patterns of diversity and demography in the North American Caesar’s mushroom species complex

Some of the effects of past climate dynamics on plant and animal diversity make-up have been relatively well studied, but to less extent in fungi. Pleistocene refugia are thought to harbor high biological diversity (i.e. phylogenetic lineages and genetic diversity), mainly as a product of increased reproductive isolation and allele conservation. In addition, high extinction rates and genetic erosion is expected in previously glaciated regions. Some of the consequences of past climate dynamics might involve changes in range and population size that can result in divergence and incipient or cryptic speciation. Many of these dynamic processes and patterns can be inferred through phylogenetic and coalescent methods. In this study, we first delimit species within a group of closely related edible ectomycorrhizal Amanita from North America (the American Caesar's mushrooms species complex) using multi-locus coalescent-based approaches; and then address questions related to effects of Pleistoce...