When up in the Cairngorms last March I carried out some stream sampling with my net. Among the cranefly larvae with scary looking jaws and the Clinging Mayfly Nymphs, were some impressive looking large stonefly larvae.
They were identified by Craig Macadam (Buglife’s Conservation Director) as Perlodes mortoni, the Orange-striped Stonefly. Until recently it was classified as the European species Perlodes microcephalus, but those in Britain were recently split into their own species, making it a British Endemic.
I got a short bit of video, showing the nymph doing ‘push ups’ presumably to increase water flow over the gills and get more oxygen.