Dialypetalum is a genus of plants endemic to Madagascar. It differs from other Lobelioideae in that it has regular (actinomorphic) flowers with virtually free petals, and is dioecious. It contains the following species, accepted as of July 2014:Dialypetalum compactum Zahlbr. Dialypetalum floribundum Benth. in G.Bentham & J.D.Hooker Dialypetalum humbertianum E.Wimm. in H.G.A.Engler Dialypetalum × hybridum E.Wimm. in H.G.A.Engler (D. compactum × D. floribundum) Dialypetalum montanum E.Wimm. in H.G.A.Engler Dialypetalum stenopetalum E.Wimm. in H.G.A.Engler