Archaeognatha
Your insect is probably a bristletail
Fact file
Order: Archaeognatha
Body length: 7 - 15mm
Species: World - 350, UK - 7
Bristletails are found almost everywhere - under stones, in leaf litter, or on rocks at the seashore. They look a bit like silverfish but have a humped body that lets them jump out of the way of predators.
