As classified in WFO snapshot
latest classification for this taxon
Allamanda cathartica var. williamsii
This variety name was first published in Cycl. Amer. Hort. 246 1933
At the time of this classification snapshot, this variety name was unplaced by WFO (a taxonomist hasn’t yet placed the name in the taxonomy). Its description and other taxonomic data can be found on World Flora Online, id: wfo-0000908713.