Chaenotheca meridionalis Tibell & Kantvilas is described as new, based on morphological characters and ITS-based phylogenetic data. Maximum Likelihood analysis was run on 62 taxa and four C. meridionalis sequences received maximum Ultrafast bootstrap support within the strongly supported ‘chrysocephala’ group. Chaenotheca meridionalis differs from its close relative, C. chlorella, by its taller apothecia, 1.04−2.04 mm high, versus 0.71–0.94 mm in C. chlorella, and wider ascospores, 3.25–4.75 μm versus 2.89–3.81 μm in C. chlorella. It inhabits decorticated wood in temperate forests and is widely distributed in Australasia. Key words: biodiversity, Coniocybomycetes, lichenised fungi, new species, molecular taxonomy.