Strongly oligolectic on Cerinthe (Boraginaceae), utilising Cerinthe minor and Cerinthe major and possibly Cerinthe glabra as pollen sources (Westrich, 1989).
The only pollen sample available so far for the Sicilian subspecies crassiclypeata contains beside pollen of Cerinthe (Boraginaceae)large quantities of monocot pollen (probably from Asphodelus or Asphodeline) (A. Müller, unpublished).
Banaszak & Romasenko (1989) also list Prunus (Rosaceae) and Cynoglossum (Boraginaceae) as forage sources.