The new species Austrella isidioidea, which is unique in the genus in having isidioid structures on the thallus lobe ends as well as apothecia lacking a thalline margin, is described from the Falkland Islands. A collection with an identical mtSSU rDNA sequence to A. arachnoidea but with significant morphological differences (viz. a variable apothecial margin ranging from an arachnoid hyphal weft to a corticated regular margin) is reported from Îles Kerguelen. The phylogenetic and biogeographical implications of these new records are discussed.
