Based on molecular and morphological evidence, a new species within Verrucariaceae, Clavascidium hispaniam-pakistanica is described from Pakistan and Spain. The taxon is characterized by thicker and slightly larger squamules with a mixed-type medulla. Additionally, it has marginal pycnidia with bacilliform conidia. We have also detected the microalga Myrmecia israelensis as the main photosymbiont in the lichens analyzed, reinforcing the often-established specificity between the lichen genus Clavascidium and the microalgae of the genus Myrmecia. Detailed comparative analyses and a microalgal discussion are provided. Keywords: Lichenized fungi · Myrmecia israelensis · New species · Taxonomy.