Oligolectic. In common with all members of the genus, visits are to Convolvulus species (Convolvulaceae)
Westrich (1989) lists the following forage sources: Convolvulus arvensis, Convolvulus cantabrica (Convolvulaceae) and Cichorium intybus (Asteraceae) purely as a nectar source
I. Cross (in litt., 2019) suggests that the nominate subspecies is found on Convolvulus arvensis, whereas, Systropha planidens grandimargo, the subspecies found in Portugal, Spain and southern France, mainly/exclusively uses Convolvulus althaeoides (apart from a nectar visit to Chicorum intybus (Asteraceae).
Records from Greece (Petanidou, PhD thesis) exist for Convolvulus althaeoides ssp. tenuissimus .
Pesenko, Banaszak et al. (2000) listing specimen data, record a male visiting Medicago falcata (Fabaceae) for nectar.