A medium-sized red and black species. Arachnospila wesmaeli belongs to the subgenus Ammosphex, in which the females have a tarsal comb to assist digging the burrow. Females are difficult to identify and require critical examination, the males have a distinct subgenital plate. Identification keys are given in Day (1988).
A very local species restricted to coastal sand dunes in England and Wales and inland heaths in the south of England. It is absent from Scotland, Ireland and the Channel Islands.
Occurs in northern and central Europe across to central Asia (Wolf 1972).