Venation predicts the location, but not the color, of forewing pattern elements in jaw moths (Lepidoptera: Micropterigidae)

Wing patterns in the order Lepidoptera are important taxonomic characters that serve various ecological functions and have long been studied by evolutionary and developmental biologists. But, although wing patterns interest biologists of many stripes, the homologies between pattern elements in different moth families and superfamilies families are still not understood. To address this fundamental gap in our current knowledge, we examined the relationship between wing pattern and wing venation in the Micropterigidae, or “jaw moths”: the most basal extant family of Lepidoptera. In the two principal genera, Micropterix and Sabatinca, we found that venation consistently predicts the location of wing pattern elements. However, the color of these wing pattern elements varies between the two genera - the dark areas traditionally called “fasciae” in Micropterix correspond to light interfascial areas in Sabatinca, and vice-versa. Our findings regarding the relationship between wing venation and wing pattern suggest that future efforts to designate homologous wing pattern elements in Lepidoptera should focus on the location of each pattern element, not the extent to which pattern elements are pigmented. Furthermore, the wing pattern of Sabatinca may shed light on the origin of complex wing patterns found in more derived Lepidoptera: when the relationship between patterning and venation is conserved, the wing pattern groundplan of Sabatinca strongly resembles that of nymphalid butterflies.