Steven Falk > Collections > Insects > Diptera (flies)

Hoverflies are the most popular group of flies within the British dipterological community and with nature-lovers in general. There are many striking even attractive species within the British fauna of about 280 species. This includes superb mimics of bees and wasps such as Pocota and Chrysotoxum, also some astonishingly cryptic species like Hammerschmidtia. British species vary in size between tiny Paragus (wing length 3.5-4mm) and the hornet-sized Volucella zonaria (wing length up to 20mm) and the build varies from broad and robust as exemplified by Volucella and Sericomyia species to incredibly delicate like Baccha elongata.

The males of many species are adept at hovering and may hold aerial territories for hours at a time. This is especially noticeable in woods during spring when species like Eristalis pertinax, Epistrophe eligans and Syrphus ribessii are particularly numerous. Others hold territories from low perches such as sunlit foliage. The holoptic eyes of most male hoverflies seem to be designed for the demands of holding a territory and spotting a female. Hoverfly courtship can be fun to observe and photograph (see images of courting Eristalis nemorum).

The biologies are just as diverse as adult appearance, for whilst about half the British species have larvae that predate aphids and their relatives (most Syrphinae and Pipizini), others develop in dead wood or tree wounds (e.g. Xylota, Chalcosyrphus, Brachypalpus, Ferdinandea, Mallota, Pocota, Myolepta, Caliprobola, Brachyopa, Callicera), as phytophagous tunnellers/grazers in plants stems, roots, tubers and leaves (most Cheilosia, Eumerus, Merodon), in dung (Rhingia), fungi (some Cheilosia), and in organically-rich water, mud, peat and decaying vegetation (e.g. Neoascia, Chrysogaster, Eristalis, Helophilus, Sericomyia, Arctophila, Syritta, Tropidia). Most Volucella species develop as scavengers in social wasp or bumblebee nests, whilst Microdon larvae inhabit ant nests and are so slug-like that they used to be classified as molluscs.

Economically, hoverflies are of huge importance. They can be the most numerous pollinators in many ecosystems - critical in ensuring you have fruit and vegetables to eat. The aphidophagous species also help suppress the numbers of pest aphids on crops and garden plants.

Many hoverfly species are useful indicators of habitat quality. With practice, you will soon be able to sense if a wood is ancient, and the pH of a wetland. There are also species assemblages associated with uplands, bogs, coastal habitats, heathland, calcareous grasslands and coniferous woodland.

FURTHER INFORMATION SOURCES:

The standard comprehensive guide to British syrphids is Stubbs & Falk (2002) ' British Hoverflies' published by BENHS, ISBN: 1899935053. This furnishes keys, species accounts and illustrations.

'Britain's Hoverflies - An introduction to the hoverflies of Britain' by Ball & Morris (2013) provides photographic coverage of 165 species, including careful presented images of critical characters and a wealth of valuable information. Published by WILDguides, ISBN: 978-0-691-15659-0.

Morris & Ball (2014) provides the current rarity gradings for our scarcer species plus species accounts: jncc.defra.gov.uk/pdf/Review_of_Syrphidae_Final_Web.pdf

Older accounts by Coe (1953, RES Handbook 10(1)) and Verrall (1901, British Flies 8. Syrphidae) are also worth seeking out because they reveal how substantially our understanding of this family has changed over the past 100 years or so and the many extra species that have been added to the British list since.

The larvae of many British species can be keyed out using Rotheray (1993) 'Colour Guide to Hoverfly Larvae', Dipterists Digest, 9.

The most useful foreign guide for British workers is 'Veldgids Zweefvliegen' (Bot & Meutter, 2019) published by KNVV, ISBN: 9789050116435 which covers all the British species plus a further 100 species that occur within Belgium and the Netherlands. Other important European works include Bartsch et. al. (2009) Tvavinger: 'Blomflugor' published by Nationalnyckeln till Sveriges Flora och Fauna, a lavish two-volume account of the Swedish fauna; also Van Veen (2004) 'Hoverflies of Northwest Europe' published by KNNV, ISBN: 9050111998

A national recording scheme for hoverflies exists and has a website: www.hoverfly.org.uk/.
and there is also a very active Hoverfly Facebook Group.

Information on Irish hoverflies is available from Ireland's National Biodiversity Data Centre:
www.biodiversityireland.ie/a-new-website-on-irelands-hove...

Much information is a also available on European hoverflies through 'Syrph the Net': pollinators.biodiversityireland.ie/hoverflies/syrph-the-net/

and:
pollinators.biodiversityireland.ie/wp-content/uploads/StN...

Further information can also be found at the Diptera.info website:
www.diptera.info/photogallery.php?album_id=49.

and Andre Schulten's photo guide:
www.natuurpunt.be/uploads/ezines/documenten/studie/fotogi....

The above are trustworthy sources of images and information but great care should be taken when using hoverfly images on the web as a very high proportion are misidentified!

Non-European syrphid websites worth checking out include the Field Guide to the Syrphidae of Northeastern North America: www.canacoll.org/Diptera/Staff/Skevington/Syrphidae/Syrph....

A more general account of hoverflies on a world basis is furnished by Rotheray & Gilbert (2011) 'The Natural History of Hoverflies' published by Forrest Text, ISBN: 9780956469212.

The images within the species sets are arranged in the sequence: males, females and habitats. If the genera are out of alphabetical sequence, it is because Flickr keeps re-arranging them!

Brachypalpus (thick-thighed forest hoverflies)

Brachypalpus...

1 album

Chalcosyrphus (wet-forest hoverflies)

Chalcosyrphus...

2 albums

Dasysyrphus (hairy-eyed syrphs)

Dasysyrphus...

6 albums

Epistrophe (neat-banded syrphs)

Epistrophe...

5 albums

Eristalinus (spotty-eyed droneflies)

Eristalinus...

2 albums

Meliscaeva (long-winged syrphoids)

Meliscaeva...

2 albums

Orthonevra (straight-veined marsh hoverflies)

Orthonevra...

3 albums

Platycheirus (big-handed hoverflies)

Platycheirus...

25 albums

Sphaerophoria (twist-tailed hoverflies)

Sphaerophoria...

9 albums

Xanthandrus (caterpillar hoverflies)

Xanthandrus...

1 album