A new species of Coccocarpia is described from Mauritius based on morphological and molecular evidence. The species is corticolous and currently known from four localities in parkland and natural mountain forest habitats. It is characterized by comparatively large thallus lobes, a distinctly pruinose upper surface, and abundant laminal isidia that are initially subspherical and later elongate into cylindrical to coralloid structures. Phylogenetic analysis of nuclear ITS rDNA sequences places the Mauritian material as a distinct lineage within Coccocarpia, not nested within any currently sampled species-level clade. The combined morphological distinctiveness and molecular differentiation support its recognition as a new species, here described as Coccocarpia aptrootii. This discovery further demonstrates that species diversity in Coccocarpia remains underestimated, particularly in tropical regions. Keywords: Indian Ocean; lichens; molecular phylogeny; new species; taxonomy.