Both Buddleja and Acantholimon are considered which level of classification?
Acantholimon Acantholimon (prickly thrift) is a genus of small flowering plants within the plumbago or leadwort family, Plumbaginaceae. They are distributed from southeastern Europe to central Asia and also in South America, but also cultivated elsewhere in rock gardens.
Buddleja 'Salmon Spheres' Buddleja 'Salmon Spheres' is a British cultivar raised by Steve Nevard, London, from a cross of "Buddleja globosa" and "Buddleja crispa".