Calyptratae
(dung, house & parasitoid flies, blue & green bottles)

KILLING

Calypterate flies are best killed by freezing. Ethyl acetate can leave them difficult to relax, although they can be set if you don’t use too much killing agent and catch them before rigor mortis sets in.

RELAXING

Calypterates are best relaxed in a jar with a few drops of vinegar on a piece of kitchen towel in the bottom. Use a squat jar such as those sold containing savoury spreads. Small insects will relax overnight, larger or stiffer ones might require a couple of days. Beware that the acetic acid will turn copper or brass-headed pins green.

SETTING

As with most flies, pull the legs down so both they and the sides of the thorax can be examined. The wings should also be positioned so they don’t obscure the abdomen, but calypterates usually die with the wings up which is OK. Male genitalia should be extruded and held open with a micropin as the specimen dries.

Most Calypterates cannot be identified from living specimens or photographs. Microscopic examination of preserved specimens is generally required.