HYMENOPTERA > APOCRITA | Aculeata > Crabronidae > Philanthinae (Philanthidae)

A medium-sized (6-12mm body length), black-and-yellow species with a yellow face, where the female has a noticeably broad S2 black abdomen segment with yellow at the base, which is followed by a predominantly yellow S3, and then with S4 having less yellow than S5. The smaller males can have more variable markings and may even have entirely black segments S4 and S5. In this respect though, it’s worth taking a close look at the mating pair in the photograph below, because not only does it show the size difference in the sexes, you can see that the female seems to have a completely black S4 segment and the male has a fair amount of yellow on S3-S6.

Cerceris rybyensis is a locally common, generally widespread species that is associated with sandy soils, both on the coast and inland, often nesting with Cerceris arenaria. It can also be found occasionally on chalk downland sites, and has a flight period from late June to early September.

Nest burrows are usually dug into level, exposed compacted soil, with the cells provisioned with various species of paralysed bees.