Rod Williams / A mating pair of conopid flies (Sicus ferrugineus), New Cross Cutting, Lewisham, England, June

Andy Sands / Bee killer fly (Myopa buccata) sitting in wait for passing Bee, Hertfordshire, England, UK, May. Focus Stacked Image

Bernard Castelein / Fly (Physocephala rufipes), Klein Schietveld, Brasschaat, Belgium. August

Rod Williams / Thick-headed Fly (Sicus ferrugineus) feeding on Bramble (Rubus) blossom, Brockley Cemetery, Lewisham, London, England, UK. May.

Rod Williams / Thick-headed flies (Sicus ferrugineus) mating pair, Brockley Cemetery, Lewisham, London, England, UK, July.

Rod Williams / Conopid fly (Myopa pellucida) on dandelion, Beverley Court Gardens, London, England, UK. April.

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

Kim Taylor / Thick-headed fly (Physocephala furcillata) on Eryingium. Surrey, England, UK, August.

Andy Sands / Conopid fly (Sicus ferrugineus) parasitic fly whose larvae are endoparasites on various species of Bumblebee, Oxfordshire, England, UK, June

Alan Williams / Thick-headed fly (Conops quadrifasciatus) resting on leaf at woodland edge Cheshire, UK, July

Rod Williams / Thick-headed fly (Conops ceriaeformis) female, Brockley Cemetery, Lewisham, London, UK. August

Rod Williams / Thick-headed fly (Sicus ferrugineus) on Ragwort Grooming Brockley Cemetery, Lewisham, London, UK. August