Callitula pyrrhogaster is a tiny, flightless parasitic wasp. Wings rudimentary, head in dorsal view only 1.8 to 1.85 times as broad as long. Abdomen (gaster) dorsally with the basal half or more reddish-orange. 

Callitula bicolor (this has wings fully developed). 

Identification of most species in this group is very difficult.  Although this particular species is rather distinctive, high quality photographs are still required.

Various habitats, grassy areas.

Main period would seem to be April to September.

A tiny parasitoid wasp of flies. A known parasitoid of the frit fly (Oscinella frit), considered a pest of agricultural crops like oats, barley, wheat, and maize.

Rarely recorded in Britain, perhaps due to its very small size and the difficulty of identifying species in this family group, but may be fairly frequent.

Rarely recorded in Leicestershire and Rutland because of identification difficulty.