Wall Mason Wasp - Ancistrocerus parietum

Females vary from 10 to 13mm, males are slightly smaller and reach a bodily length of 8 to 11mm. Ancistrocerus parietum, A. gazella and A. quadratus are all very similar and hard to separate without detailed examination. The basic colour is black, with yellow bands, and they have a very narrow waist.

Usually seen visiting nesting holes, sometimes there a numerous holes in a suitable bank or wall.

May to September peaking around July.

Nests in any suitable cavity, from small holes in old walls, to holes in tree trunks or soil banks. The prey of this genus is lepidopterous caterpillars.

Fairly common and found in England, Wales, south Scotland and Ireland.

Fairly common in Leicestershire and Rutland.