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Cluster Fly

Cluster Flies

Pollenia rudis/Musca autumnalis/Dasyhora caynella

The cluster fly makes it’s appearance in autumn and are commonly found in large numbers in south facing buildings which they use to over-winter. Although they do not cause damage they are a nuisance pest.

Found in lofts and roof spaces usually in the south facing side of a building. It is usually found that buildings that have Cluster fly do so on a yearly basis.

Pollenia rudis

are slightly larger than the common house fly, Musca domestica . These have yellow hairs on the thorax which gives a golden appearance even though they are brown/grey in colour.
Musca autumnalis are a similar size to the common house fly. They are grey with four dark stripes on the thorax.
Dasyhora caynella are again a similar size to the common house fly. They are a metallic blue/green in colour. 


Cluster flies, Pollenia rudis in particular are very common throughout the UK.

The adult Cluster fly emerge from their winter hide out in spring to lay their eggs in soil. When hatched the larvae, which are parasitic, seek out earthworms on which they feed until they emerge as adult flies in early autumn.