Ignatov, M.S., O.I. Kuznetsova, E.A. Ignatova & V.E. Fedosov. 2024. On the genus Dicranoweisia (Rhabdoweisiaceae, Bryophyta) in Russia

Arctoa (2025) 34: 52–60

doi: 10.15298/arctoa.34.05

The genus Dicranowesia includes in Russia one species, D. cirrata, with a limited distribution in its most western regions: in Kaliningrad Province and the Black Sea coastal area in the Caucasus. Despite of quite few known populations of the species in Russia, they comprise two clearly differentiated phenotypes, which also differ in the nuclear ITS sequences. The first ribotype is widespead in the world: it includes plants from the western North America, West Europe eastwards to the Baltic Sea region, some parts of the Caucasus, and East Africa. The second ribotype is known in Russia from a restricted area in the North Caucasus, with rather dry Mediterranean vegetation dominated by Juniperus & Pistacea. This second ribotype has a limited Old World Mediterranean distribution in Turkey, Greece, Tunisia, Morocco, and Canary Islands. The widespread ribotype is rare in Russia but potentially may expand its range, since it occurs sometimes in man-made habitats, while the population of the ‘Old World Mediterranean’ ribotype requires a conservation concern. Plants of the latter are morphologically distinct: they have short capsules and poorly differentiated costa, usually lacking stereids. The same two traits were used as diagnostic for D. africana, described from Rwanda, however one sequenced collection of this species from Tanzania belongs to the widespread ribotype.