B. subser. Sphaerocarpae was formally defined as containing those taxa with "seeds with transversely aligned cells on the inner face on the inner face of the wing,... and old styles that curl loosely around the infructescence." In addition, all species except B. grossa have a papery interseminal plate. The epithet Sphaerocarpae is taken from the specific epithet of the type species, B. sphaerocarpa (Fox Banksia).[1]
The wide phyletic separation of B. sphaerocarpa var. dolichostyla (Ironcap Banksia) from the other varieties of B. sphaerocarpa prompted Thiele to promote it to species rank as B. dolichostyla.[1]
The placement and circumscription of B. subser. Leptophyllae in Thiele and Ladiges' arrangement may be summarised as follows:[1]
- Banksia
- B. subg. Isostylis (3 species)
- B. elegans (incertae sedis)
- B. subg. Banksia
- B. ser. Tetragonae (4 species)
- B. ser. Lindleyanae (1 species)
- B. ser. Banksia (2 subseries, 12 species)
- B. baueri (incertae sedis)
- B. lullfitzii (incertae sedis)
- B. attenuata (incertae sedis)
- B. ashbyi (incertae sedis)
- B. coccinea (incertae sedis)
- B. ser. Prostratae (8 species)
- B. ser. Cyrtostylis (4 species)
- B. ser. Ochraceae (3 species, 2 subspecies)
- B. ser. Grandes (2 species)
- B. ser. Salicinae (2 subseries, 11 species, 4 subspecies)
- B. ser. Spicigerae (3 subseries, 7 species, 6 varieties)
- B. ser. Quercinae (2 species)
- B. ser. Dryandroideae (1 species)
- B. ser. Abietinae
- B. subser. Nutantes (1 species, 2 varieties)
- B. subser. Sphaerocarpae
- B. grossa
- B. dolichostyla (now B. sphaerocarpa var. dolichostyla)
- B. micrantha
- B. sphaerocarpa
- B. s. var. sphaerocarpa
- B. s. var. caesia
- B. subser. Leptophyllae (4 species, 2 varieties)
- B. subser. Longistyles (6 species, 2 varieties)
Thiele and Ladiges' arrangement remained current only until 1999, when George's treatment of the genus for the Flora of Australia series of monographs was published. This was essentially a revision of George's 1981 arrangement,[2] which took into account some of Thiele and Ladiges' data, but rejected their overall arrangement. B. subser. Sphaerocarpae was discarded, as were the other three subseries of B. ser. Abietinae, and B. dolichostyla was once more demoted to a variety of B. sphaerocarpa.[3]
