THE CHEMISTRY AND SYSTEMATIC IMPORTANCE OF THE GREEN WING PIGMENT IN EMERALD MOTHS (LEPIDOPTERA, GEOMETRIDAE, GEOMETRINAE)

The green colour in the wings of Emerald Moths (Geometridae: Lepidopte ra) was found to be caused by a single pigment, here termed geoverdin. Contrary to previous suggestions, it is not a bile pigment; there is some evidence that geoverdin is a derivative of chlorophyll. The pigme nt molecule is highly labile and eluded identification. However, after resolving problems of extracting this acid- and light-sensitive subst ance from the wing scales (inert, exocuticular structures), we found t hat profiling by thin layer chromatography (TLC) provided a sensitive and cost effective comparative technique for identifying the pigment i n a wide range of Lepidoptera. With the possible exception of two gene ra, geoverdin occurs as the primary pigment only within the Geometrina e, although it exists in trace quantities in certain other Lepidoptera . Our comparisons suggest that the presence of large quantities of geo verdin in Geometrinae is an apomorphic character for the subfamily, al though its occurrence in two anomalous genera suggests that it may not have evolved uniquely. More generally, we recommend the use of TLC pr ofiling as an invaluable technique for systematic studies involving in sect pigments.