Relationship between the maximum pronotum width and maximum head width (a, b), and relationship between the maximum pronotum width and hind tibia length (c, d) of female (a, c) and male (b, d) Euborellia species (Euborellia sp. 1 and Euborellia sp. 3). Red, blue, and black symbols represent samples from Malaysia, the main islands of Japan (Honshu, Shikoku, and Kyushu, and Shimokoshiki Island near Kyushu), or Ioto Island, respectively. The data of a female E. annulata, collected from Basse-Terre Island, Guadeloupe Archipelago, is also shown in a and c (light blue crossed diamonds). Details of the localities are provided in Suppl. material 2.