As this is a cleptoparasitic species, all flower visits will be for nectar only.
Westrich (1989) lists the following nectar sources in Germany: Echium vulgare, Anchusa officinalis (Boraginaceae); Thymus serpyllum, Mentha sp., Stachys recta (Lamiaceae); Knautia arvensis (Dipsacaceae); Centaurea jacea, Helichrysum arenarium (Asteraceae)
Celary (1990) lists the following nectar sources in Poland: Anchusa officinalis, Echium vulgare (Boraginaceae); Thymus serpyllum (Lamiaceae); Centaurea (Asteraceae).
Mavromoustakis (1948; 1952) recorded visitation to Cirsium syriacum, Centaurea cilicica, Centaurea hyalolepis, Dittrichia (=Inula) viscosa (Asteraceae); Limonium (=Statice) virgata (Plumbaginaceae); Marrubium vulgare apolum, Nepeta troodi (Lamiaceae); Eryngium creticum (Apiaceae) and Echium sericeum, Heliotropium villosum (Boraginaceae) in Cyprus
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