Distribution of Psylliodes attenuata and its Humulus spp. host plant. Jurisdictions where P. attenuata has been documented are indicated by grey (Döberl 2010) and blue shading (Vietnam and South Korea, records from GBIF and CNC). Green points indicate georeferenced P. attenuata specimens. Purple shading indicates the range of Humulus spp. in North America and Eurasia, based on GBIF records. The blue line is the approximate -25.5°C minimum isotherm, which corresponds to the coldest average monthly temperature for any of the P. attenuata records.