Pterostigma

Wing of a dragonfly, showing the pterostigma
Wings of a snakefly

The pterostigma (plural: pterostigmata) is a group of specialized cells in the outer wings of insects, which are often thickened or coloured, and thus stand out from other cells. It is particularly noticeable in dragonflies, but present also in other insect groups, such as snakeflies, hymenopterans, and megalopterans. It is also often referred to as a stigma.[1]

  1. ^ "Definition of Pterostigma". Amateur Entomologists' Society. Retrieved 20 September 2010.