Cullumia is a small genus of spiny, thistle-like shrubs in the daisy family (Asteraceae), placed in the tribe Arctotideae and subtribe Gorteriinae alongside related South African genera. The genus was established by the Scottish botanist Robert Brown in 1813, in the second edition of Hortus Kewensis (vol. 5, p. 137), with Cullumia ciliaris (Willd.) R.Br. as the type species. Roughly 15 species have been described under the genus, all restricted to the Cape Province of South Africa, making it one of many genera endemic to the extraordinarily biodiverse Cape Floristic Region. The common name "snakethistles" reflects the plants' stiff, spiny leaves and thistle-like appearance, characteristics shared with others in the Gorteriinae subtribe. Like their relatives in tribe Arctotideae — which includes the well-known African daisies (Arctotis) — Cullumia species bear composite flower heads typical of Asteraceae, though details of floral colour and head size vary across species. The genus is not widely cultivated and remains primarily of interest to botanists and enthusiasts of South African fynbos flora.
Etymology
The genus name Cullumia was given by Robert Brown in 1813 to honour Sir Thomas Gery Cullum (1741–1831), 7th Baronet, a British surgeon and amateur botanist from Bury St Edmunds who was a Fellow of the Royal Society and the Linnean Society, and who published a privately printed English flora in 1774. According to Wikipedia, the name also commemorates his brother, Sir John Cullum, 6th Baronet, a clergyman and antiquary.
Distribution
All species of Cullumia are endemic to the Cape Province of South Africa, as stated by Wikipedia. This places the genus entirely within the Cape Floristic Region, one of the world's six major floral kingdoms, recognised for its exceptional plant diversity and high endemism.
Taxonomy Notes
Cullumia was described by Robert Brown in 1813 in Hortus Kewensis, ed. 2, vol. 5: 137. The type species is Cullumia ciliaris (Willd.) R.Br. Within Asteraceae, the genus is placed in subfamily Vernonioideae, tribe Arctotideae, subtribe Gorteriinae. GBIF recognises approximately 6 accepted species under the primary checklist node, while other checklist datasets list up to 25 named taxa. The synonym Cullumia R.Br. (with explicit authorship) appears in GBIF alongside the accepted name, reflecting nomenclatural tracking of the original description.
