Banksia aquilonia formed a clade with B. plagiocarpa, B. oblongifolia and B. robur, rather than B. integrifolia. Early in 2007, Mast and Thiele rearranged the genus Banksia by merging Dryandra into it, and published B. subg.
Banksia aquilonia was part of a clade with other species like B. plagiocarpa, B. oblongifolia, and B. robur, but not B. integrifolia. In 2007, Mast and Thiele reorganized the genus Banksia by merging Dryandra into it, leading to the creation of a new subgenus for Banksia.