Bernard Castelein / Fly (Eriothrix rufomaculata), KLein Schietveld, Brasschaat, Belgium. June

Rod Williams / Ladybird fly (Gymnosoma rotundatum) a rare / localised species Brockley Cemetery, Lewisham, London, England, UK. May.

Jiri Lochman / Snail parasite blowfly (Amenia imperialis) Cape Tribulation, North-eastern Queensland, Australia.

Lucas Bustamante / Ecuadorian toadhead (Bothrocophias campbelli) with Mosquito (Culicidae) feeding on its head, Mindo, Pichincha, Ecuador.

Nick Upton / Swift lousefly (Craeterina pallida), a blood sucking parasite unique to swift nests, found on a Swift chick (Apus apus) and held in the hands of a bird ringer, Worlington, Suffolk, UK, July. Model rel...

Andy Sands / Tachnid 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 / Tachnid 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

Paul Bertner / Fruit Fly (Tephritidae) pair mating, with mite on back, Gunung Leuser National Park, Sumatra, Indonesia

Paul Bertner / Fruit Fly (Tephritidae) with fungal infection, Ankarafantsika National Park, Madagascar

Rod Williams / Parasitic fly (Conops quadrifasciatus) parasite of Red-tailed Bumblebee Brockley cemetery, Lewisham, South East London, England, UK, August.

Kim Taylor / Parasite fly (Tachina fera) on Eryngium. Surrey, England, UK, August.

Kim Taylor / Tachinid fly (Dexiosoma caninum). Surrey, England