There are 34 species of stonefly in Britain, which are common around fast-flowing streams and rivers, where the larvae spend their lives hiding amongst the gravels and feeding on algae and plants. The adults hatch out, usually in the summer, and do not travel very far from the stream: they are often found on riverside rocks and trees.

How to identify

Stoneflies are fairly robust invertebrates with narrow, dark wings, long antennae and two stout tail bristles. Stonefly larvae can be recognised by having two 'tails' and by their habit of clinging to the undersides of rocks in fast-flowing water.

Where to find it

Various species found throughout the country.

When to find it

  • January
  • February
  • March
  • April
  • May
  • June
  • July
  • August
  • September
  • October
  • November
  • December

How can people help

Stonefly larvae and adults are food sources for many species, providing a vital link in the food chain. The Wildlife Trusts recognise the importance of healthy habitats to support all kinds of species throughout the food chain, so we are working towards a Living Landscape: a network of habitats and wildlife corridors across town and country, which are good for both wildlife and people. You can support this greener future by joining your local Wildlife Trust.

Species information

Common name
Latin name
Other insects
Body length: 1-2.5cm
Conservation status
Mostly common. Northern February Red and Scarce Yellow Sally stoneflies are classified as Priority Species in the UK Biodiversity Action Plan.