Siphocampylus nebularis is a new species endemic from the Serra do Mar mountain range in the Paraná state, Brazil. It is morphologically close to S. fulgens due its alternate phyllotaxis, sparsely denticulate leaves, and flowers with reddish corolla tube, differing mainly by the shorter corolla tube, longer calyx lobes, and coriaceous leaves observed in the new species. The new taxon is here described and illustrated. We also propose the inclusion of S. nebularis in the IUCN Red List as an endangered (EN) species due its narrow distribution and the decline of the quality of its habitat.