the females have mated they start to dig their short burrows and create cells with walls made of a thin and transparent material which resembles cellophane in appearance and which is formed from a secretion produced in the Dufour's gland located in the bee's abdomen. The main food plants are heathers, especially ling Calluna vulgaris and the females have been recorded travelling up to 1.5 km from the nest to collect pollen to provision the cells. They have also been recorded foraging on Erica, ivy and Asteraceae as well as melilot (Melilotus sp.), yarrow (Achillea millefolia) and creeping thistle (Cirsium arvense). In Spain it has also been recorded feeding on Daphne gnidium and dwarf gorse (Ulex minor). Alternative pollen sources to Calluna vulgaris are mainly used once the pollen of that species starts to run low in late summer. Parasites and predators Colletes succinctus nests are commonly cleptoparasitized by the cuckoo bee Epeolus cruciger. They may also be parasitized by the sarcophagid fly Miltogramma punctata while adults have been recorded as being predated by the crabronid wasp Cerceris rybyensis. Taxonomy and phylogeny Colletes succinctus is a member of the succinctus species complex within the genus Colletes. There are 12 species which are currently assigned to the succinctus species group which includes the Mediterranean species Colletes intricans from North Africa as well as C. collaris and C. brevigena from more southerly areas of Europe. The three western European species C. halophilus, C. hederae and C. succinctus appear to be particularly closely related, so much so that the former two were only identified as separate species from C. succinctus in the 20th Century. They are almost indistinguishable from each other both phenotypically and genetically but are separated ecologically. The oldest species is thought to be C. succinctus and the distribution of this species closely matches that of its food plant. It is also parasitized by the cuckoo bee Epeolus cruciger with which it is largely sympatric. The other two species have distributions which lie within that of C. succinctus and do not closely match the distributions of their food plants while the cuckoo bee E. cruciger still uses them as hosts but it does not do so with the efficiency that it does with C. succinctus. This strongly suggests that C. succinctus is the "parent" of C. halophilus ad C. hederae and that these two species arose from populations of C. succinctus