Tachysphex aethiops is a primarily western species that also occurs in the Upper Peninsula of Michigan. Females nest in mossy, sand slopes and utilize pre-existing burrows of other insects. One shallow, five-celled nest contained a single, third-instar nymph of Spharagemon sp., probably bolli, in each cell. Three prey were parasitized by miltogrammine flies.
O'Brien, Mark F.
"Biology and Distribution of Tachysphex Aethiops in Michigan (Hymenoptera: Sphecidae: Larrinae),"
The Great Lakes Entomologist, vol 20
Available at: https://scholar.valpo.edu/tgle/vol20/iss2/4