Caddis flies 4

Polycentropidae family

The larvae, (see Polycentropus sp. above) are carnivorous web spinners with no abdominal gills, but 5 anal gills. They have large anal appendages with terminal hooks. They live inside a silk web and do not construct a case. They are found in all types of water except fast flowing. There are 13 British species.

On the left is Polycentropus sp. a fully grown larva is about 12 mm long. They are found in rivers and lake edges, and are sometimes found in groups.

The Philopotamidae family

The larvae have orange or yellow-brown, narrow heads. In this family the larvae catch their food (mainly diatoms and detritus) in long, tubular bag-nets which have a very fine mesh. There are 5 British species.

Above is Philopotamus sp.

Limnephilidae family.

The Limnephiliidae have 55 U. K. species; more than any other family. Many of the species are difficult to identify, but some can be identified from the structure of the larval case.

The larvae make their cases out of a variety of materials. They are found in stagnant or slow- moving water. Quite often the case is so heavy that the larva cannot swim, but only crawls around. The total length on the case above is about 15 mm.

Odontoceridae family

On the left is Odontocerum albicorne, also known as the Silver sedge . It makes its nest out of grains of sand, and is found in fast flowing bouldery rivers. There is just one British species in this family.

Adults have a wing length of 13 - 18 mm, and the antennae are longer than the fore wing. Adults fly from June - September in the afternoon and evening.