A Note on the Pterostigma in Insects

Abstract

During studies on blood circulation in the wings of insects it was observed incidentally that the pterostigma (“stigma” of some authors) in some insects had little in common with the similarly-termed structure in others. At the same time some of them were structurally similar to areas not generally identified as pterostigmata in the wings of other species. In view of the general recognition of pterostigmata as an obvious feature in certain insect wings, the apparent mis-interpretation of their nature, and their possible significance in wing evolution, it seems useful to comment on their structure and possible origins.