The Prevalence and Manifestation of Wing De-melanization in the Eastern Carpenter Bee (Hymenoptera, Apidae Xylocopa virginica) Associated with Urban Areas

Abstract

Animals that live in urban environments face unique stressors due to increased temperatures associated with these novel ecosystems. Large bees in the family Apidae thermoregulate in a variety of fashions including wing muscle vibrations, basking, and collecting heat with the wings. Thus, the coloration of the wing will impact the degree of heat absorption. The eastern carpenter bee, Xylocopa virginica Linnaeus, is a widespread, univoltine species found throughout eastern North America. Typically, X. virginica has solid dark brown to black wings. We report on a newly discovered wing phenotype in which the wing has lost significant amounts of coloration, making them nearly transparent. Using specimens from St. Louis, MO, we found that the de-melanization is usually restricted to the distal portions of the wing, yet the coverage differs between individuals. The proportion of individuals exhibiting pigment loss is similar between males and females. We examined observations on the iNaturalist platform and found that the phenotype is found in urban areas throughout the species range. We hypothesize that de-melanization could be an adaptation to heat stress, however more research is needed.