70 UK species, 25 genera, 6 families. Lacewings are delicate, slow and leisurely flying insects which are readily attracted to light at nighttime. They rest with their net-like wings folded in a tent-like fashion over their bodies, and they can have very bright-shining eyes, and are somtimes referred to as ‘Golden Eyes’. The most likely encounter with a lacewing will be with a green lacewing, but there are also the brown lacewings, which are smaller, duller and less conspicuous. Many species of lacewing, the adults and larvae, are fierce hunters and avid feeders of aphids, so are always welcome in the garden to help keep pests down. Some larvae are very clever and they will disguise their bodies with debris and the empty skins of their prey as camouflage. We also have the spongeflies whose larvae are aquatic and feed on freshwater sponges. We must also not forget the tiny waxflies, which are known for the powdery coating of wax on their body and wings. This group also includes 1 species of ant-lion called Euroleon nostras, the only one of its kind in the British Isles. Lacewings can be discovered in hedgerows, woodland, meadows, parks and gardens. Care must be taken when identifying this group of insects as many look very similar to one another, and usually require microscopic examination of the genitalia or magnification of the wing venation.
For further reference see the links and literature below:
Useful AIDGAP reference book: A Key to the adults of British Lacewings and their allies by Colin W. Plant.