In the potter wasp genus Parancistrocerus, the base of the second metasomal tergite is concave, and covered by the posterior lip of the first metasomal tergite, and mites are carried in the concavity.
The specific characteristics of the potter wasp genus Parancistrocerus include a concave area on its second metasomal segment that is protected by the posterior edge of the first metasomal segment. This concavity serves as a habitat for mites.