Belongs to: flies

Caddisfly many species


Best time to see: all year

Key facts

Moth-like insects forming a large group known as Trichoptera, mostly associated with fresh water

The young play an important role in freshwater ecology, keeping the water clean by feeding on leaves and other debris

Britain has about 200 species

Recognition

Adults have four wings, folded tent-like over the abdomen when at rest, and long antennae

The larvae live in fresh water, some using silk to bind together materials such as twigs or sand to form a protective case

Weak fliers, on the wing mainly in late afternoon and at night; up to 65mm wingspan and 20mm body

Lifecycle

The lifecycle is annual, the larvae staying under water to feed through autumn and winter before entering the pupal stage

They spin a cocoon within their case to pupate and emerge from the water in late spring or summer

Adults only last a few weeks, feeding little if at all, mated females laying eggs on plants near to the water surface

  • Main photo

Photo © Tony Gunton