Predicted distribution and climate envelope comparison
The distribution of G. platensis in South America could be driven by an expansion into novel environments. Thus, our ENM approach focused on evaluating areas of potentially suitable climate that the species could invade. This model had good performance and obtained a true positive fraction of 98% across all known unique localities of the invaded range (AUC = 0.956, BI = 0.883; Fig. 3). Notably, the ENM predicted highly suitable climates for G. platensis in the Andes of Colombia, Ecuador, and Northern Peru. The coastal portion Chile, from Santiago to Puerto Montt, also showed high suitability, whereas areas at the southeast of Brazil and Uruguay, east Argentina and the Andes of Bolivia showed intermediate suitability. In Ecuador, we found three areas of high suitability in the northern (where we collected the specimens analyzed in this study), central and southern parts of the Ecuadorian Andes. Comparison of climate envelopes of the four top contributing climatic factors and elevation for Ecuador and the rest of South America highlighted some variation in the occupied niches (Table 1; Fig. 4). For example, the range of G. platensis in Ecuador revealed significant climate envelope differences related to seasonality and elevation (Table 1; Fig. 4). Across South America, these beetles occupy a wide breadth of climatic conditions and elevations. They exist in elevational ranges spanning low and high altitudes, from 7 m to 3351 m above sea level (a.s.l.). In Ecuador, G. platensis occupies the highest elevational range with a mean of ca. 2600 (2233–3351) m a.s.l. (Fig. 4). The lowest elevation ranges were found in Argentina, Chile, and Uruguay, generally found from 7 to 327 m a.s.l.