Ignatov, M.S., A.V. Fedorova, E.I. Ivanova & E.A. Ignatova. 2024. Didymodon gaochienii (Pottiaceae, Bryophyta) in Russia

Arctoa (2024) 33: 61–70

doi: 10.15298/arctoa.33.08

Didymodon gaochienii, a species described from Qinghai Province of China, is found in Yakutia (NE Asian Russia). This species was recently placed into synonymy of D. fragilicuspis, but the new molecular phylogenetic data challenge this decision. The new Yakutian specimen is almost identical with the type of D. gaochienii in nrITS1-2 sequence, and they differ contrastingly from all other sequences obtained from plants of Didymodon with fragile leaf tips. Taking into account the great distance, ca. 5100 km, between Qinghai and Yakutian localities, and the identity of Yakutian and Chinese specimens both in sequences and morphology, we suggest a reconsideration of species delimitation in this group.