The species is a social parasite primarily of Bombus lapidarius. On occasions, it may also parasitize Bombus sichelii (Rasmont, 1988). There are also records of nest usurpation of Bombus sylvarum and Bombus pascuorum (Løken, 1984) and Bombus pratorum (Peeters, Raemakers & Smit, 1999).
Celary (1989) cites Bombus lapidarius, Bombus sylvarum and Bombus pascuorum as hosts.