*2.1. Location Data for E. japonica*

The complete list of locations (longitude and latitude) for distribution of *E. japonica* in China was collected from the Global Biodiversity Information Facility (GBIF, http://www.gbif.org/), and the Chinese Virtual Herbarium (CVH) databases (http://v5.cvh.org.cn/). A few distribution records were obtained by literature searches and our field investigations. We assessed the dataset under a set of criteria based on the suggestions of Boitani et al. [25]. Only the specimens collected in the last 20 years and documented in the literature during that time period were used. Furthermore, only locations provided by online search engines or local flora were used to ensure that these locations represent areas of permanent and natural presence. The analysis excluded records with imprecise locations when no exact geo-coordinates existed in the location records. After duplicates were removed, the remaining points were filtered to ensure that only one point was plotted per 1.0 × 1.0 km grid cell. A total of 195 geological reference records were collected (Figure 1).

**Figure 1.** Known sites of *Euscaphis japonica* used when generating the predictive models. Provinces and other administrative areas are outlined.
