Cluster-fly
Guides
Pollenia angustigena
Narrow-cheeked Clusterfly
Pollenia angustigena is a medium-sized cluster fly in the family Polleniidae, measuring 4.5–9.5 mm. Formerly classified in Calliphoridae, this species is now placed in Polleniidae based on morphological and molecular evidence. Adults display variable coloration with chequered abdominal dusting and distinctive golden crinkly thoracic hairs. The species is widely distributed in Britain and parts of continental Europe, with records from Belgium, Denmark, Norway, and Portugal (Madeira). Adults are active from March to October, though they may be recorded year-round indoors during winter. Like other Pollenia species, adults feed on flower nectar and may contribute to pollination, while larvae are parasitoids or predators of earthworms.
Pollenia griseotomentosa
cluster fly
Pollenia griseotomentosa is a Palaearctic cluster fly and the smallest British species in the genus Pollenia, measuring 4.5–8.0 mm in body length. It is distinguished from congeners by specific morphological characters including lack of pale wing tuft, yellow to pale brown posterior thoracic spiracle lappets, dark palpi and basicosta, and characteristic bristle patterns. Like other cluster flies, adults overwinter in sheltered locations including buildings, where they aggregate in large numbers and may become nuisance pests. The species has been introduced to North America, with records from Canada and the northeastern United States.
Pollenia labialis
cluster fly
Pollenia labialis is a species of cluster fly in the family Polleniidae. It is one of several Pollenia species introduced to North America from Europe, likely arriving in the 1950s or 1960s. Like other cluster flies, it is associated with earthworms as larval hosts. The species is distinguished from congeners by microscopic characters including the number, position, and length of setae on various body parts. It is considered a nuisance pest when adults enter buildings to overwinter.
Pollenia pediculata
Tufted Clusterfly, cluster fly
Pollenia pediculata is a species of cluster fly in the family Polleniidae, distinguished by golden crinkly hairs on the thorax and a tuft of pale hairs at the wing vein junction. The species is native to the Palaearctic region and has been introduced to multiple continents including North America, South Africa, Australasia, and New Zealand. Adults are important pollinators that feed on flowers and are attracted to fish bait and carrion, though they do not breed in carrion. The species is notable for its winter aggregations indoors, earning the common name "cluster fly."
Pollenia rudis
common cluster fly, attic fly, loft fly, buckwheat fly
Pollenia rudis, the common cluster fly, is a medium-sized blow fly in the family Polleniidae. Adults are notable nuisance pests of buildings, overwintering in attics and wall voids in large aggregations during cold months. The species is an obligate parasite of earthworms in its larval stages, with well-documented host specificity to certain lumbricid species. Native to Europe, it has been introduced to North America and New Zealand, where it occurs wherever its earthworm hosts are present.
Pollenia vagabunda
cluster fly
Pollenia vagabunda is a cluster fly in the family Polleniidae, widespread across Europe and introduced to North America, where it was first recorded in 1958. Unlike carrion-associated blow flies, this species has a life cycle tied to earthworms and other hosts rather than decomposition. Adults are known to overwinter in buildings and have been documented on carrion, though not tied to specific decomposition stages. The species has also been recorded in Algeria and shows potential forensic relevance.