
thumb|300px|Wing of a dragonfly, showing the pterostigma thumb|Wings of a snakefly
thumb|300px|Wing of a dragonfly, showing the pterostigma thumb|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.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).