Draeculacephala crassicornis

A green species with pale blue venation. Morphologically quite similar to D. angulifera and D. noveboracensis , there are two dark spots in front of the antennal segments and two very close dark spots on the vertex. Importantly, however, are the antennae which have a distinctly black and expanded tip as if flattened (this is more pronounced in males than in females). Clear views of various angles are necessary to determine the species. This species usually has shorter wings than similar species, but this is not always the case. Key features of the male 3S apodemes and aedeagus used by Hamilton (1985) to differentiate his species and subspecies (here considered synonyms of D. crassicornis ) vary among individuals within and among collection lots and do not consistently define subsets of specimens. I have been unable to find discrete morphological differences among these taxa. Although differences in voltinism have been documented among two possibly allopatric populations of D. crassicornis in Oregon (Swenson and Kamm, 1975) ( D. crassicornis and D. bivoltina of Hamilton, 1985), crossbreeding experiments have not been performed, and it is not known whether intervening populations that exhibitt intermediate periods of reproduction exist. Thus, until further work elucidates the extent of morphological and ecological differences among univoltine and bivoltine populations of D. crassicornis , I regard them as one species. - Dietrich, 1994