Is a newly reported presence of Stictis radiata in Svalbard a result of global climate change, or is it due to the availability of a suitable substrate?

The identification of materials collected in Svalbard led to the discovery of the species Stictis radiata (L.) Pers. This species is a facultatively lichenized fungus and an epiphyte whose main range lies outside the Arctic. We collected two specimens of this species in the Colesdalen, Svalbard. This place is one of ‘Arctic hotspot complexes’, as Arve Elvebakk called them, where the only place in the archipelago with growing Betula nana is located. Colesdalen also had suitable conditions of moisture and “sheltered” from the winds for the formation of sufficiently large woody remains of vegetation, which became a suitable substrate for Stictis radiata, whose main range is confined to the forest zone. The closest known locations of the species are in the Pechenga region of the Murmansk Region (Russia) and Scandinavia. This article discusses the ecological preferences and distributional features of the species.