Pentas was previously treated more broadly, with many more species (Verdcourt, 1953). However Kårehed & Bremer (2007) separated several genera based primarily on molecular characters. Two of these genera are now documented from Madagascar, Pentas and Phyllopentas. Both of these are also found in continental Africa, but no species are shared between there and Madagascar. Most of Madagascar's species now belong to Phyllopentas.
!CMT, V 2011