The stoneflies above and below are in the Perlodidae family. The double ladder can be seen, but the antennae are blurred as they were in constant movement.
Above and below is Leuctra sp. This genus is also known as needle flies because of the way the wings are folded around the body when at rest. All stoneflies in this family are relatively small, and the adults have short cerci.
Above is an adult in the Nemouridae family. All in this family are fairly small - less than 12 mm as adults - and their cerci are either short or inconspicuous.
Family Perlidae. This family have the largest nymphs of all U. K. stoneflies. They are relatively large and fat, and up to 35 mm long. They have a pair of white feathery gills at each of the 3 segments of the thorax.
Above is the nymph of Perla maxima, the largest species. It is most commonly found in hill streams.