Oncosiphon sabulosus stem-tips

The erect Oncosiphon sabulosus stem-tips are broad and flat-topped, the elaborately dissected leaves clustered densely. The leaves are often very pointy, particularly along their lateral margins.

The inflorescences emerge over the upper leaves, each head on a fairly short peduncle. The numerous disc florets are tightly together, arranged in elegant Fibonacci curves within each head, spirals that grow apparently exponentially. 

There are no ray florets. The bisexual, yellow florets start off as mere dots in bud, their opening commencing from the perimeter of the head, the innermost ones performing last, if they get the chance (Bond and Goldblatt, 1984; Kolokoto, R and AR Magee (2018): Cape stinkweeds: Taxonomy of Oncosiphon. SA Journal of Botany, pp 57 – 70; iNaturalist; https://www.fernkloof.org.za; http://redlist.sanbi.org).