Nick Upton / Beach fly (Calliopum sp.) basking on a leaf, Wiltshire garden, UK, June.

Solvin Zankl / Wild type Common fruit flies (Drosophila melanogaster) from laboratory culture, the flies were fed with green and red food for staining purposes, Vienna Drosophila RNAi Center, Institute for Molecula...

Mary McDonald / Little Green Bee-eater (Merops orientalis) with fly prey. Kanha National Park, Madhya Pradesh, India.

MYN / Piotr Naskrecki / Long legged fly (Condylostylus sp) Concord, Massachusetts, USA, June. meetyourneighbours.net project

MYN / Piotr Naskrecki / Long legged fly (Condylostylus sp) Concord, Massachusetts, USA, June. meetyourneighbours.net project

Robert Thompson / Cleg fly (Haematopa pulvialis) adult at rest on bog myrtle, County Antrim, Northern Ireland, UK, July

Ole Jorgen Liodden / Orca (Orcinus orca) playing with almost dead Green Sea-turtle (Chelonia mydas agassisi) as sea birds fly above. Galapagos

Ernie Janes / Green bottle flies (Eudasyphora cyanella) feeding on cow dung, Norfolk, UK, August

Ernie Janes / Green bottle flies (Eudasyphora cyanella) feeding on cow dung, Norfolk, UK, August

Andy Sands / Tachinid fly (Phasia hemiptera) male, the female lays its eggs directly onto Forest Bugs and Green Shield Bugs where the larvae live as parasites, Hertfordshire, England, August

Andy Sands / Tachinid fly (Phasia hemiptera) male, the female lays its eggs directly onto Forest Bugs and Green Shield Bugs where the larvae live as parasites, Hertfordshire, England, August

Nick Upton / Bluebottle fly (Calliphora vicina) feeding on Ivy flowers (Hedera helix) with extended proboscis, sponging up nectar with disc-like labellum. Wiltshire garden, UK, September

Nick Upton / Greenbottle / Muscid fly (Eudasyphora cyanella), preparing to take off from a Variegated mock orange (Philadelphus coronarius "aureus") leaf. Wiltshire, UK, June

Andy Sands / Hornet (Vespa crabro) feeding on rotting apple alongside Green-bottle fly. West Sussex, UK, October.

Nick Upton / Two male Greenbottle flies (Eudasyphora cyanella) competing with one another as they search for mates. This is an overwintering species. Wiltshire, UK, March

Russell Cooper / Flesh Fly (Sarcophaga carnaria) portrait at rest on grass stem, South London, England, UK

Nick Upton / Male Green / Broad centurion soldier fly (Chloromyia formosa) feeding from Common hogweed / Cow parsnip (Heracleum sphondylium) flowers. Wiltshire, UK, June.

Nick Upton / Deer fly (Silvius alpinus) with green eyes nectar feeding from flowers, Pyrenees, Spain

Stephen Dalton / Hoverfly (Helophilus pendulus) amongst duckweed on pond surface, UK

Stephen Dalton / Green meadow spider (Micrommata virescens) with flesh fly prey, UK, Sparassidae

Stephen Dalton / Green meadow spider (Micrommata virescens) feeding on hover fly, UK, Sparassidae

Nick Upton / Green / Broad centurion soldier fly (Chloromyia formosa) female with very obvious halteres, Wiltshire, UK, June

Shattil & Rozinski / Green jay (Cyanocorax yncas) preparing to fly, Lower Rio Grande Valley wildlife corridor, South Texas, USA

Rolf Nussbaumer / Green Bottle Fly, Lucilia / Phaenicia sericata} adult, Hill Country, Texas, USA

Rolf Nussbaumer / Green Lynx Spider {Peucetia viridans} adult on Golden Crownbeard flower (Verbesina encelioides)feeding on Hover Fly, Rio Grande Valley, Texas, USA,

Piotr Naskrecki / Green-eyed Fly (Scione sp) on human skin showing compound eyes, Guyana

Piotr Naskrecki / Green-eyed Fly (Scione sp) portrait showing compound eyes, Guyana

Piotr Naskrecki / Green-eyed Fly (Scione sp) portrait showing compound eyes, Guyana

Pete Oxford / Lantern fly on tree trunk (Fulgoridae) Amazonia, Ecuador

Kerstin Hinze / Spanish fly / Blister Bee (Lytta vesicatoria) Bulgaria

Piotr Naskrecki / Green and Black Poison Dart Frog (Dendrobates auratus) on a leaf next to the largest Fly in the world, tropical Americas

ZSSD / Venus Fly Trap (Dionaea muscipula) carnivorous plant, native to South America

Kim Taylor / Green orb web spider {Araniella cucurbiina} in web in Ox-eye daisy with flies.

Kim Taylor / Crane flies {Tipulidae} mating. UK.

Duncan Mcewan / Gadfly eyes close-up, UK

Duncan Mcewan / Gadfly on leaf, UK

John Cancalosi / Green lynx spider {Peucetia viridans} predating fly on cactus plant, Texas, USA

Michael & Patricia Fogden / Banded King Shoemaker (Prepona demophon) catterpillar anterior body expanded to expose false eye spots and mimic snake, note eggs of parasitic Tachinid fly, rainforest, Costa Rica

Mark Moffett / Stag Fly (Phytalmia cervicornis) small male has only small knobs instead of full antlers, Papua New Guinea

Piotr Naskrecki / Green Mantisfly (Zeugomantispa minuta), Solon Dixon Forestry Education Center, Alabama

Barry Mansell / Long legged fly (Chrysosoma sp) on leaf, North Florida, USA, August.

Premaphotos / Common green colonel soldier fly (Oplodontha / Odontomyia viridula) in a marsh, UK

Premaphotos / Glittering green fly (Poecilobothrus nobilitatus), male grooming his genitals, UK

Duncan Mcewan / Tiger beetle with fly prey {Cicindela campestris) Scotland, UK

Andy Sands / Broad centurian soldier fly (Chloromyia formosa) male, portrait, Hertfordshire, England, UK. June. Focus stacked.

Andy Sands / Broad centurian soldier fly (Chloromyia formosa) female, resting on a leaf, Hertfordshire, England, UK. June. Focus stacked.

Guy Edwardes / Green drake mayfly (Ephemera danica) resting on dew-covered grass, Rhodope Mountains, Bulgaria. June.

Michael Hutchinson / Flower crab spider (Misumena vatia) female, on flower clutching Greenbottle fly (Lucilia sericata) prey, Bristol, UK. June. Focus stacked.

Michael Hutchinson / Flower crab spider (Misumena vatia) female, on flower clutching Greenbottle fly (Lucilia sericata) prey, Bristol, UK. June.

Kim Taylor / Wasp (Vespula sp.) worker flies past a Common fleabane (Pulicaria dysenterica) and then spots a Clouded yellow butterfly (Colias croceus) which it perceives as potential prey. The wasp moves round the...

Guy Edwardes / European pond turtle/terrapin (Emys orbicularis) swimming in pond with head above water and a fly resting on its snout, near Bratsigovo, Bulgaria, May

Neil Aldridge / Little bee-eater (Merops pusillus) perched, watching insects as they fly past. The animal takes off, after its prey and then returns with an insect which it swallows. Okavango Delta, Botswana.

Guy Edwardes / Long-legged fly (Poecilobothrus nobilitatus) male resting on leaf, Powerstock Common Nature Reserve, Dorset, England, UK. June.

Will Watson / Pond olive mayfly (Cloeon dipterum) nymph, close up, Lugg Rhea, Herefordshire, England, UK. August. Controlled conditions.

Andy Sands / Scorpion fly (Panorpa communis) resting on Bluebell (Hyacinthoides non-scripta) flowerhead. Hertfordshire, England, UK. May. Focus Stacked.

Andy Sands / Common red-legged robberfly (Dioctria rufipes) resting on grass stem. Hertfordshire, England, UK. May. Focus Stacked.

Andy Sands / Green drake mayfly (Ephemera danica) roosting at dawn covered in dew. Hertfordshire, England, UK. June. Focus Stacked.

Andy Sands / Green drake mayfly (Ephemera danica) roosting at dawn covered in dew. Hertfordshire, England, UK. June. Focus Stacked.

Andy Sands / Fly (Coenosia sp) resting on leaf, at dawn covered in heavy dew. Hertfordshire, England, UK. June. Focus Stacked.

Andy Sands / Violet black-legged robberfly (Dioctria atricapilla), male, resting on grass stem. Oxfordshire, England, UK. June. Focus Stacked.

Andy Sands / Violet black-legged robberfly (Dioctria atricapilla), male, feeding on prey. Oxfordshire, England, UK. June. Focus Stacked.

Andy Sands / Stripe-backed snailkiller fly (Limnia unguicornis), female, in typical head down pose on grass. Buckinghamshire, England, UK. May. Focus Stacked.

Andy Sands / Stripe-backed snailkiller fly (Limnia unguicornis), male, in typical head down pose, with rain drops on grass. Buckinghamshire, England, UK. May. Focus Stacked.

Andy Sands / Stripe-backed snailkiller fly (Limnia unguicornis), male, climbing back up grass after rainy shower. Buckinghamshire, England, UK. May. Focus Stacked.

Andy Sands / Pair of St Mark's flies (Bibio marci) mating on grass stem. Hertfordshire, England, UK. May. Focus Stacked.

Andy Sands / Splayed deer fly (Chrysops caecutiens), male, feeding on yellow flower. Hertfordshire, England, UK. July.

Andy Sands / Splayed deer fly (Chrysops caecutiens), male, feeding on yellow flower. Hertfordshire, England, UK. July.

Andy Sands / Splayed deer fly (Chrysops caecutiens), male, feeding on yellow flower. Hertfordshire, England, UK. July.

Andy Sands / Pair of Long hoverflies (Sphaerophoria scripta) mating on grass stem. Hertfordshire, England, UK. July.

Andy Sands / Snail-killing fly (Pherbellia cinerella) in typical head down pose on grass stem with rain drops. Buckinghamshire, England, UK. May. Focus Stacked.

Andy Sands / Blue long-horned snailkiller fly (Sepedon sphegea), male, in typical head down pose on sedge stem. Buckinghamshire, England, UK. May. Focus Stacked.

Andy Sands / Blue long-horned snailkiller fly (Sepedon sphegea), male, in typical head down pose on sedge stem. Buckinghamshire, England, UK. May. Focus Stacked.

Juergen Freund / Slow motion clip of male Birdwing butterfly (Ornithoptera priamus) resting on a leaf before a bee interupts it, and they both fly away, Australia.

Guy Edwardes / Grey drake mayfly (Ephemera danica) resting on reed, Powerstock Common, Dorset, UK, May.

Guy Edwardes / Green drake mayfly (Ephemera danica) resting on Wild onion (Allium vineale), Sturminster Newton, Dorset, UK, June.

Guy Edwardes / Snipe fly (Rhagio scolopacea) perched on leaf, Dorset, UK, June.

Guy Edwardes / Green drake mayfly (Ephemera danica) at sunset, River Frome, Dorchester, Dorset, UK, June.

Guy Edwardes / Yellow dung fly (Scathophaga stercoraria) perched on dead grass, Dorchester, Dorset, UK, May.

Andy Sands / Broad centurion soldierfly (Chloromyia formosa) roosting at dawn and covered in dew, Hertfordshire, England, UK, July - Focus Stacked

Chris Mattison / Hoverfly (Syrphus ribesii) male, a wasp mimic, resting on leaf with small bugs.

Neil Aldridge / Close up of domestic cattle (Bos taurus) noses surrounded by flies, Cornwall, England, UK, October.

Neil Aldridge / Close up of domestic cattle (Bos taurus) noses surrounded by flies, Somerset, England, UK, August.

Neil Aldridge / Close up of Domestic Cattle (Bos taurus) faces surrounded by flies, Somerset, England, UK, August.

Neil Aldridge / Close up of domestic cattle (Bos taurus) chewing whilst surrounded by flies, Somerset, England, UK, August.

Phil Savoie / Greenbottle fly (Lucilia sericata), Monmouthshire, Wales, UK, February.

Andy Rouse / Common mayfly (Ephemera danica) against setting sun, Wales, UK.

Guy Edwardes / Fly agaric fungus (Amanita muscaria). New Forest National Park, England, UK. October.

Nick Upton / Large red damselfly (Pyrrhosoma nymphula) male eating a Green drake mayfly (Ephemera danica) head first on a river bank reed, Wiltshire, UK, May.

Nick Upton / Green drake mayfly (Ephemera danica), newly emerged on a riverside reed, Wiltshire, UK, May.

Nick Upton / Green drake mayfly (Ephemera danica), newly emerged on a riverside reed, Wiltshire, UK, May.

Nick Upton / Banded demoiselle damselfly (Calopteryx splendens) male eating a Green drake mayfly (Ephemera danica) on a river bank plant, Wiltshire, UK, May.

Georgette Douwma / Greenbottle (Lucilia caesar) flies on a chicken bone. UK.

Georgette Douwma / Greenbottle (Lucilia caesar) flies on a chicken bone. UK.

David Tipling / Mayfly (Ephemera danica) resting on stem. Little Ouse, near Brandon, Norfolk, England, UK. May.

David Tipling / Mayfly (Ephemera danica) resting on blade of grass. Little Ouse, near Brandon, Norfolk, England, UK. May.

Chris Mattison / Mayfly, (Ephemera danica), Catbrook, Monmouthshire, Wales, UK.