Mason. Nesting site: The free standing nests are constructed in depressions or surface irregularities of stones, rocks or walls with 2-8 cells. The species also uses small cavities in stony substrates containing only one brood cell.
Nesting material: Entire cells are made from pebbles cemented together with mud. The nest is covered by an outer coat of mud. In small stone or rock cavities, the orifice is closed with a layer of mud. (Benoist, 1931; Blüthgen, 1920; Stoeckhert, 1933; Westrich, 1989; M. Herrmann and A. Müller, personal observation)