Rhinacanthus spiciformis, a new species of Acanthaceae from northern Vietnam

Rhinacanthus spiciformis Y. F. Deng, Z. L. Lin & D. V. Hai, a new species from northern Vietnam previously misidentified as R. calcaratus is described and illustrated. This new species differs from all other Asian species of Rhinacanthus in the inflorescence being unbranched or comprised of trifurcate‐branched spikes, and the lower lip of corolla with conspicuous purple stripes near throat and on lobes. The pollen morphology and chromosome number are presented. It is proposed to be accessed as Least Concern (LC) according to the IUCN categories and criteria.