Mud wasps in Chiang Mai province making tubular entrances to their nest −open mud-tubes that form straight chimneys above the nest's holes− in order to raise the entrances above the surrounding vegetation.

The tube is composed of a series of little pellets of sand and mud, which the wasps stick together with the help of their mouth secretions, until a kind of open mud-tube is formed (fig.), akin to Organ Pipe Mud Daubers.