Cleptoparasitic: Host: In Britain, this species is almost certainly a cleptoparasite of Heriades truncorum, the well-known host on the continent (Friese, 1895b; Blüthgen, 1919; Bischoff, 1927; Blüthgen in Schmiedeknecht, 1930; F.K. Stöckhert, 1933; van der Zanden, 1982; Westrich, 1983; Banaszak & Romasenko, 1998; Peeters, Raemakers & Smit, 1999). H. truncorum is itself a scarce bee in Britain,confined mainly to south-east England; it has been found in all the sites where S. breviuscula has been recorded in Britain. The host species nests in burrows in decaying wood and in dry, broken pithy stems, including Rubus. The majority of British specimens have been found at rest on wooden fence posts (Else & Edwards, 2018).
Elsewhere in mainland Europe, the species is reported to be a cleptoparasite of Chelostoma species and Hoplitis adunca (Banaszak & Romasenko, 1998; Matache & Ban, 2006; Stanisavljević, 2000).
Celary (1989) and Baldock et al. (2018) additionally cite Heriades crenulata as a host.
Kasparek (2015) reports records from Ukraine of parasitism of Heriades crenulata. Kasparek (citing others) also lists Osmia rapunculi and Hoplitis adunca.