John Abbott / Wasp (Pteromalus puparum), parasitoid wasp of butterfly pupae including Monarch butterflies (Danaus plexippus) Brackenridge Field Laboratory, Austin, Travis Co, Texas, USA, December.

Nick Upton / Chalcid wasp (Pteromalus sp.) a parasite of Leafcutter bees (Megachile sp.), inspecting host nest burrows in an insect hotel, Wiltshire garden, UK. July.

Nick Upton / Wood-carving leafcutter bee (Megachile ligniseca) nest cell with an exit hole chewed out in spring, probably by emerging parasitic Chalcid wasps (Pteromalus sp.), whose larvae develop inside Leafcutte...

Jiri Lochman / Parasitic wasp (Thaumasura sp.) female, portrait, Fitzgerald River National Park, Western Australia. November. (Pteromalidae)

Jiri Lochman / Galls formed by Gall wasp (Trichilogaster acaciaelongifoliae), Peak Charles National Park, Western Australia. October. (Pteromalidae)

Jiri Lochman / Galls formed by Gall wasp (Trichilogaster acaciaelongifoliae), Peak Charles National Park, Western Australia. October. (Pteromalidae)

Jiri Lochman / Parasitic wasp (Thaumasura sp.) male, on tree bark, Chaelundi National Park, New South Wales, Australia. September. (Pteromalidae)

John Abbott / Butterfly pupal parasite wasp (Pteromalus puparum) having just emerge, Brackenridge Field Laboratory, Texas, USA. (Pteromalidae).

Alex Hyde / Chalcid Parasitoid Wasp (Pteromalidae, probably Mesopolobus tibialis). 2mm in length, found moving over opening oak buds. Peak District National Park, Derbyshire, UK. April. Focus Stacked Image.

Alex Hyde / Chalcid parasitoid wasp (probably Mesopolobus tibialis), 2mm in length, moving over Oak (Quercus sp.) buds, Peak District National Park, Derbyshire, UK. April. Focus Stacked Image.

Doug Wechsler / Parasitoid wasp (Pteromalid sp.), a hyperparasitoid, parasitizing parasitoids on aphids, Philadelphia, Pennsylvania, USA. June.