Xanthoparmelia perezdepazii from the Canary Islands is described as new to science. It is characterized by an isidiate upper surface, the presence of usnic, constipatic and protoconstipatic acids in the medulla and a brown lower surface.

Xanthoparmelia isidiovagans and X. subverrucigera from Spain are described as new to science. Both species are characterized by an isidiate upper surface and the presence of the stictic acid chemosyndrome in the medulla, but X. isidiovagans has a vagrant thallus with markedly revolute lobes with a black lower surface, whereas X. subverrucigera has adnate thalli with subirregular lobes and a brown lower surface.

Eight new species of Xanthoparmelia (Parmeliaceae) are described from eastern Australia: X. biloelensis Elix, X. fracticollis Elix, X. kosciuszkoensis Elix, X. nerrigensis Elix, X. paratasmanica Elix, X. rankinensis Elix, X. remanella Elix and X. stuartioides Elix. In addition, a further ten new state records of Xanthoparmelia are reported from eastern Australia.

The following new species of Xanthoparmelia (Parmeliaceae) are described from Western Australia: X. cranfieldii Elix, X. elevata Elix, X. kimberleyensis Elix, X. monadnockensisX. nanoides Elix, X. nortegeta Elix, X. sleei Elix and X. toolbrunupensis Elix. In addition, X. luminosa (Elix) Hale and X. Victoriana Elix & J. Johnst. are reported from Western Australia for the first time.

The following new species of Parmeliaceae are described from Africa: Xanthoparmelia bainskloofensis Elix & T. H. Nash, X. boyeri Elix, X. dubitella Elix, X. kleinswartbergensis Elix, X. lobuliferella Elix, X. malawiensis Elix, X. micromaculata Elix and X. waboomsbergensis Elix. The new combination Xanthoparmelia patula (Brusse) Elix is made and X. hypoleiella Elix, X. neoconspersa (Gyeln.) Hale, X. neocumberlandia T. H. Nash & Elix and X. sipmanii T. H. Nash & Elix are reported from Africa for the first time.

Eleven Xanthoparmelia species have been identified from Italy. A key to the species is provided and the distinguishing morphological and chemical characters, distribution, ecology, substratum preference and interrelationships of each are discussed. Xanthoparmelia cumberlandia is reported for the first time from Europe; X. angustiphylla and X. plittii are new to Italy.