On 26 April 2018, four members of the expert committee on lichens visited Fridö and Furholmen Nature Reserve near Tullgarn Castle. The purpose was to clarify the status of the false golden lichen Psora testacea, reported from Furholmen in 1895, which is the only reported finding of the species on the mainland. The species was not found and in the absence of any evidence, our proposal is that the report of this species from Södermanland is too uncertain to be validated. A species list including the species recorded from Fridö is presented. Eleven species are reported as new to Södermanland, i.e. Briancoppinsia cytospora, Calogaya arnoldii, Catillaria cryptophila, Endocarpon pusillum, Gyalidea subscutellaris, Muellerella erratica, Rinodina lecanorina, Scytinium aragonii, Verrucaria dolosa, V. macrostoma and V. tectorum.