1. Centro de Investigação em Biodiversidade e Recursos Genéticos (CIBIO-UP), and Universidade do Porto4485-661 Vairão, Portugal
2. Division of Biological Sciences, University of MontanaMissoula, MT 59812, USA
3. USDA Forest Service, Rocky Mountain Research StationMissoula, MT 59801, USA
4. National Park Service, Rocky Mountain NPEstes Park, CO 80517, USA