Caddis Fly – Report Records

21st June 2013 – Mystacides azurea is like all caddis flies a species that lives under the water in a case when in its larval stage. The flying adult is about 6 to 9 mm long and has bluish black wings which have a characteristic fold at the distal extremity, making the rear of the wing look very angular when viewed from above. This caddis fly is in the family Leptoceridae which all have antennae which are threadlike and extremely long, approximately twice the length of the body. The males have distinctly larger eyes than the females. The species M. azurea being red eyed but other similar species have black. They have distinctive large hairy maxillary palps which are used in mating. A swarm of circa.50 were below Whillet’s bridge on 16/6/13 performing low water flying with vertical zigzag movements. A female, when approaching a swarm, is caught by a male which holds her around the abdomen with its long black maxillary palps and both use their wings to fly in tandem to the shore where they copulate. The aquatic stages are found in shallow marginal areas of lakes and ponds or slow moving tracts of streams. They are omnivorous feeding on plant detritus as well as other arthropods and quite common and widespread in Britain.

 Caddis Flies

8th July 2013 – Further to the Caddis fly observations of Mystacides azurea in June, another of the genus  Mystacides was seen.  This species  Mystacides longicornis  (also known as Grousewing)  was photographed near Whillet’s Pool on 8th July 2013. Longicornis can be identified by its three sooty bands. The life cycle and habits for all the caddis fly genus Mystacides are very similar.  In the attached picture it’s black grasping angled claspers can be clearly seen.

Grousewing Caddis Fly

3rd May 2015 – A moth box occasionally used for moth surveys was used on this date which attracted these two caddis flies. Its a known fact most adult caddis fly species do fly in the early part of the night and many are attracted by lights. Identification of caddis flies can be difficult as the markings on some species like Cinnamon Sedge can be very variable. The mottled sedge can be identified by its indented wing end shape and black tip marking. Both species mentioned are considered to be common.

Fig. 1 – Cinnamon Sedge Caddis Fly species

Cinnamon Sedge Caddis Fly

Fig. 2 – Mottled Sedge Caddis Fly

Mottled Sedge Caddis Fly