Fig 1.
Maximum likelihood tree of Usnea longissima haplotypes using the fungal ITS barcoding marker.
Bootstrap values are given for supported branches (> 70). Black dots indicate Asian voucher samples (all others North America and one from Europe). Scale bar indicates rate of changes per site. The ingroup sequences of the JX978-series are individual haplotypes representing a total of 1477 sequenced specimens, with each sequence representing a selected specimen corresponding to that particular haplotype.
Fig 2.
Best fitting MexEnt model for Usnea longissima based on 1477 sequenced samples corresponding to 160 localities from Rolstad et al. (2013), indicated by shaded areas ranging from pale blue-green to red.
Bright blue areas indicate range of predicted absence. Map is overlayed by occurrence records from GBIF (white dots), and those falling outside the predicted range are marked with red circles. One dot may include more than one GBIF record (S1 Table).
Fig 3.
Global mapping of absolute distance scores derived from the first axis of a PCA ordination of environmental grid parameters used for the predictive niche modeling.
Distances were computed from an optimal environmental parameter set defined by the highest AUC values for grids with predicted distribution of Usnea longissima. Blue areas indicate zero or short ecological distances from the optimal grid whereas red areas indicate far distances (ecogeographical barriers). The tropics emerge as a strong barrier for the north-south distribution of the species.
Table 1.
Factor loadings of the environmental variables used in the PCA and total variance explained.
High loadings of >0.70 are highlighted in boldface and marked with an asterisk.
Table 2.
GenBank Accession numbers and voucher information for specimens of Usnea longissima used in the phylogenetic and predictice modeling analysis.