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.
Cultivar group A cultivar group – represented in a botanical name by the symbol Group or Gp (previously cultivar-group) – is a formal category for cultivated plants that share a defined characteristic according to the "International Code of Nomenclature for Cultivated Plants" ("ICNCP"). "Group" or "Gp" is always written with a capital "G" in a botanical name, or "epithet". The cultivar group is not italicized in a plant's name. The "ICNCP" introduced the symbol "Group" in 2004, as a replacement for the lengthy and hyphenated "cultivar-group", which had previously been the category's name since 1995. The non-standard abbreviation cv. group is also sometimes encountered.