Cluster fly

Genus of flies

Cluster flies are flies of the genus Pollenia in the family Polleniidae. Unlike the more familiar blow flies, such as the bluebottle genus Phormia they do not lay eggs in human food. They parasitise earthworms; the females lay their eggs near earthworm burrows, and the larvae then feed on the worms. But the biology of this group is relatively poorly known and a few have been recorded from other hosts including caterpillars and bees.

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