Cleptoparasitic: Hosts; A cleptoparasite of apparently two or more Megachile species. In the NHML there is a female reared from a nest of M. centuncularis collected in Dyfed by O.W. Richards. Stelfox (1927) states that a few specimens were reared from a nest of M. versicolor found in the roof of a house in Down. In the West Country, R.C.L. Perkins (1923, 1924) also lists these two Megachile species as hosts of this bee. Chambers (1949) observed a female flying about an elm log in company with M. ligniseca in Bedfordshire.
In the Netherlands it is reported as a cleptoparasite of Megachile centuncularis and M. lapponica (van der Zanden, 1982). M. centuncularis is also recorded on the Continent as a host of this species by Jørgenson (1921), Bischoff (1927) and Peeters, Raemakers & Smit (1999). Peeters, et al. also cite M. versicolor and M. alpicola as hosts. Banaszak & Romasenko (1998), copied by Stanisavljević (2000) and Matache & Ban (2006) additionally cite Hoplitis papaveris as a host