Cluster flies (a.k.a. grass flies or attic flies) are flies of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

''Pollenia'' in the family

Polleniidae Polleniidae is a family of flies in the order Diptera. There are at least 6 genera and more than 190 described species placed definitively in Polleniidae, and other genera whose placement here is considered uncertain. The largest genus is '' Pol ...

. Unlike the more familiar

blow flies The Calliphoridae (commonly known as blow flies, blow-flies, carrion flies, bluebottles, greenbottles, or cluster flies) are a family of insects in the order Diptera, with almost 1,900 known species. The maggot larvae, often used as fishing b ...

, such as the bluebottle genus ''Phormia'', they are completely harmless to human health because they do not lay eggs in human food. They are parasitic on

earthworm An earthworm is a terrestrial invertebrate that belongs to the phylum Annelida. They exhibit a tube-within-a-tube body plan; they are externally segmented with corresponding internal segmentation; and they usually have setae on all segments. Th ...

s; 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.Jewiss-Gaines, A. et al. Cluster Flies (Calliphoridae: Polleniinae: Pollenia) of North America
/ref> Cluster flies seek refuge in cold weather and find their way into attic spaces and similar areas indoors. They often emerge on warm days, and cluster at windows attempting to exit (hence the name). The typical grass fly '' Pollenia rudis'' is about 7 mm long and can be recognised by distinct lines or stripes behind the head, short golden-coloured hairs on the

thorax The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the cre ...

, and irregular light and dark gray areas on the

abdomen The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. ...

. Cluster flies are typically slow-moving. Cluster flies have a widespread distribution. Eight species are found in

Britain Britain most often refers to: * The United Kingdom, a sovereign state in Europe comprising the island of Great Britain, the north-eastern part of the island of Ireland and many smaller islands * Great Britain, the largest island in the United King ...

and 31 in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

. ''Pollenia'' species are also numerous in

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

and

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

(over 30 species); they are common in

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

. ''P. rudis'' has spread widely in association with humans.

Species

*'' P. advena'' Dear, 1986 *'' P. aerosa'' Dear, 1986 *'' P. agneteae'' Rognes, 2019 *'' P. alajensis'' Rohdendorf, 1926 *'' P. amentaria'' (

Scopoli Giovanni Antonio Scopoli (sometimes Latinized as Johannes Antonius Scopolius) (3 June 1723 – 8 May 1788) was an Italian physician and naturalist. His biographer Otto Guglia named him the "first anational European" and the "Linnaeus of the Au ...

1763 Events January–March * January 27 – The seat of colonial administration in the Viceroyalty of Brazil is moved from Salvador to Rio de Janeiro. * February 1 – The Royal Colony of North Carolina officially creates Meck ...

) *'' P. angustigena'' Wainwright, 1940 *'' P. antipodea'' Dear, 1986 *'' P. astrictifrons'' Dear, 1986 *'' P. atramentaria'' ( Meigen, 1826) *'' P. atricoma'' Dear, 1986 *'' P. atrifemur'' Malloch, 1930 *'' P. bartaki'' Rognes, 2016 *'' P. bezziana'' Rognes, 1992 *'' P. bicolor'' Robineau-Desvoidy, 1830 *'' P. bulgarica'' Jacentkovsky, 1939 *'' P. calamisessa'' Hardy, 1932 *'' P. chotei'' Kurahashi & Tumrasvin, 1979 *'' P. commensurata'' Dear, 1986 *'' P. consanguinea'' Dear, 1986 *'' P. consectata'' Dear, 1986 *'' P. contempta'' Robineau-Desvoidy, 1863 *'' P. cuprea'' Malloch, 1930 *'' P. dasypoda'' Portschinsky, 1881 *'' P. demissa'' ( Hutton, 1901) *'' P. dysaethria'' Dear, 1986 *'' P. dyscheres'' Dear, 1986 *'' P. dysethria'' Dear, 1986 *'' P. enetera'' Dear, 1986 *'' P. erlangshanna'' Feng, 2004 *'' P. eurybregma'' Dear, 1986 *'' P. flindersi'' Hardy, 1932 *'' P. fulviantenna'' Dear, 1986 *'' P. fulvipalpis'' Macquart 1835 *'' P. fumosa'' ( Hutton, 1901) *'' P. griseotomentosa'' (Jacentkovsky 1944) *'' P. grunini'' Rognes, 1988 *'' P. haeretica'' Séguy, 1928 *'' P. hazarae'' ( Senior-White, 1923) *'' P. hirticeps'' Malloch, 1927 *'' P. hispida'' Dear, 1986 *'' P. huangshanensis'' Fan & Chen, 1997 *'' P. hungarica'' Rognes, 1987 *'' P. ibalia'' Séguy, 1930 *'' P. immanis'' Dear, 1986 *'' P. insularis'' Dear, 1986 *'' P. japonica'' Kano & Shinonaga, 1966 *'' P. labialis'' Robineau-Desvoidy 1863 *'' P. lativertex'' Dear, 1986 *'' P. leclercqiana'' (

Lehrer Lehrer, alternatively Lehr, Lehrian or Lehrmann, is a surname that can be either Germanic or Jewish. Origin Teacher The most probable option for the origin of the Lehrer surname is from the word ''Lehrer'', meaning teacher or rabbi in the Germ ...

1978) *'' P. limpida'' Dear, 1986 *'' P. luteovillosa'' Rognes 1987 *'' P. margarita'' Schluesslmayr & Sivell, 2021 *'' P. mayeri'' Jacentkovsky 1941 *'' P. mediterranea'' Grunin 1966 *'' P. mesopotamica'' Mawlood & Abdul-Rassoul, 2009 *'' P. moravica'' (Jacentkovský, 1941) *'' P. moretonensis'' Macquart, 1855 *'' P. mystica'' Rognes, 1988 *'' P. nigripalpis'' Dear, 1986 *'' P. nigripes'' Malloch, 1930 *'' P. nigrisquama'' Malloch, 1930 *'' P. nigrita'' Malloch, 1936 *'' P. notialis'' Dear, 1986 *'' P. opalina'' Dear, 1986 *'' P. oreia'' Dear, 1986 *'' P. paragrunini'' Rognes, 1988 *'' P. paupera'' Rondani, 1862 *'' P. pectinata'' Grunin, 1966 *'' P. pediculata'' Macquart 1834 *'' P. pernix'' ( Hutton, 1901) *'' P. ponti'' Rognes, 1991 *'' P. primaeva'' Dear, 1986 *'' P. pseudintermedia'' Rognes, 1987 *'' P. pseudomelanurus'' (Feng, 2004) *'' P. pulverea'' Dear, 1986 *'' P. rudis'' ( Fabricius, 1794) *'' P. ruficrura'' Rondani, 1862 *'' P. rufifemorata'' Rognes & Baz, 2008 *'' P. sakulasi'' (Kurahashi, 1987) *'' P. sandaraca'' Dear, 1986 *'' P. scalena'' Dear, 1986 *'' P. semicinerea''

Villeneuve Villeneuve, LaVilleneuve or deVilleneuve may refer to: People * Villeneuve (surname) Places Australia * Villeneuve, Queensland, a town in the Somerset Region Canada * Circuit Gilles Villeneuve, a Formula One racetrack in Montréal * Villeneuv ...

, 1911 *'' P. shaanxiensis'' Fan & Wu, 1997 *'' P. sichuanensis'' Feng, 2004 *'' P. similis'' (Jacentkovsky, 1941) *'' P. stigi'' Rognes, 1992 *'' P. stolida'' Malloch, 1936 *'' P. tenuiforceps'' Séguy, 1928 *'' P. townsendi'' Senior-White, Aubertin & Smart, 1940 *'' P. umbrifera'' (

Walker Walker or The Walker may refer to: People *Walker (given name) *Walker (surname) *Walker (Brazilian footballer) (born 1982), Brazilian footballer Places In the United States *Walker, Arizona, in Yavapai County *Walker, Mono County, California * ...

, 1861) *'' P. uniseta'' Dear, 1986 *'' P. vagabunda'' ( Meigen 1826) *'' P. venturii'' Zumpt, 1956 *'' P. vera'' Jacentkovsky, 1936 *'' P. verneri'' Rognes, 1992 *'' P. viatica'' Robineau-Desvoidy, 1830 *'' P. viridiventris'' Macquart, 1847

References

External links

Images
of some cluster fly species: ''Pollenia amentaria'' Scopoli ; ''Pollenia angustigena'' Wainwright and ''Pollenia rudis''Fabricius.
European including Russia species
* https://www.biodiversitylibrary.org/item/35035#page/322/mode/1up {{DEFAULTSORT:Cluster Fly Polleniidae Articles containing video clips Diptera of Europe Diptera of Asia Diptera of Australasia Taxa named by Jean-Baptiste Robineau-Desvoidy