Two new genera in the subfamily Teloschistoideae (Teloschistaceae, Teloschistales) are described: Hosseusiella-S. Y. Kondr., L. Lokos et A. Thell for the Caloplaca chilensis group including three South American species and Rehmanniella S. Y. Kondr. et J.-S. Hur for the new species, R. wirthii S. Y. Kondr. from South Africa. The new genera are supported by a three-gene phylogeny based on ITS1/ITS2 nrDNA, 28S nrLSU, and 12S mtSSU sequences. The new taxonomic position of Elixjohnia ovis-atra in the subfamily Teloschistoideae is discussed. The two new species Hosseusiella gallowayiana and Rehmanniella wirthii are described, illustrated and compared with closely related taxa. Hosseusiella gallowayiana is recorded for the first time as the host for the lichenicolous fungus Arthonia tetraspora S. Y. Kondr. A key to the species -of Hosseusiella is included, as well as new information of the related genus Follmannia. The following new combinations are proposed: Hosseusiella chilensis (Karnefelt, S. Y. Kondr., Froden et Arup) S. Y. Kondr., L. Lokos, Karnefelt et A. Thell, Hosseusiella pergracilis (Zahlbr.) S. Y. Kondr., L. Lokos, Karnefelt et A. Thell and Elixjohnia ovis-atra (Sochting, Sogaard et Sancho) S. Y. Kondr. Key words: Elixjohnia, Follmannia, Hosseusiella, Hosseusiella gallowayiana, key, new genera, new species, phylogenetic analysis, Rehmanniella, Rehmanniella wirthii, South Africa, South America, Teloschistaceae, Teloschistoideae