Sex-Related Color Patterns in Elytral Vittae of Diabrotica Virgifera Virgifera (Coleoptera: Chrysomelidae)

We evaluated the color patterns of elytral vittae by sex in adults of Diabrotica virgifera virgifera leConte. Our study examined >1000 beetles taken from a field population, a laboratory colony, and a reference collection containing 712 specimens from 15 of the United States and from the province of Ontario, Canada. The humeral and sutural vittae of each beetle's elytra were classified as being separate, partially confluent, or totally confluent with each other. The distribution of these elytral patterns was not independent of sex. Males tended to have confluent or partially confluent vittae, whereas females largely had separate vittae. Nonetheless, all three patterns of elytral vittae were found in both sexes of D. v. virgifera, and many beetles of each sex had partially confluent vittae. This data shows that sexing D. v. virgifera beetles by simple examination of elytral vittae alone is unreliable.