Tillingbourne Riverfly Monitoring

We have identified two different species of caseless caddis at Albury:

• Rhyacophilidae

• Hydropsychidae.

They are both reasonably large (growing up to approximately 15mm) and quite easy to identify. We find them in our sample throughout the year.

Rhyacophilidae are greenish in colour with bunches of brownish/red gills along the sides. They are free-living and don't make a shelter until ready to pupate.

Hydropsychidae are darker in colour and live in a shelter of debris and stones with a net in the front. When disturbed they move fairly quickly and hold there abdomen in a pronounced curve.

Rhyacophilidae