Renter: Existing cavities. Cavities under or between stones and rock fissures; in dense grass tussocks. The cells are built singly or in small groups of up to five or more cells closely beside each other.
Nesting material: The cells, which are not glued to the substrate, are three-layered: the outer and inner layer consist of large pieces of petals (e.g. of Geranium, Helianthemum, Hieracium, Ononis), the central layer is built of mud intermixed with small pebbles. In narrow cavities, the space in front of the cells is sometimes filled with earth crumbs up to a length of 0.5cm. (Amiet et al., 2004; Banaszak and Romasenko, 2001; Benoist, 1931; Ferton, 1897; Müller et al., 1997; Rozen et al., 2010).