Excavator: Stems. The females excavate the pith of dry stems. The nests are constructed in a linear fashion, and the cell partitions and entrance plug are made of leaf mastic.
Excavated burrows in pithy stems (e.g. Ferula, Cirsium, Cynara, Verbascum, Onopordum, Dipsacus, Rubus, Artemisia and others). The females are able to enter the pithy core of the stems by biting a hole from the side through the wooden wall. Nesting material: The cell partitions are made of masticated leaves, sometimes mixed with pith. The nest plug consists of several layers of leap pulp alone or of leaf pulp mixed with pith. The emergence of the adults often takes place through a holes chewed in the side of the stem. (Banaszak and Romasenko, 2001; Benoist, 1931; Dufour and Perris, 1840; Enslin, 1925, 1933; Friese, 1923; Graeffe, 1902; Grandi, 1961; Le Goff, 1997; Malyshev, 1937; Müller et al., 1997; Westrich, 1989)