Published online by Cambridge University Press: 30 July 2021
A new fruticulose species, Polycauliona comandorica, is described from the supralittoral zone of the Commander Islands in the Russian Far East. This growth form is very rare in the family Teloschistaceae where the new species belongs. It is the only fruticulose species of the family that forms vegetative propagules (soredia and blastidia). Polycauliona comandorica is similar to the North American P. thamnodes but differs in having a lighter yellow to grey thallus, longer and thicker branches with a rough surface, soredia and blastidia, and in lacking apothecia. Two fruticulose-lobate pairs of species in Polycauliona are briefly discussed: P. comandorica-P. verruculifera and P. thamnodes-P. brattiae.