Gymnocolea borealis (Anastrophyllaceae, Marchantiophyta) in Asia and Russia: morphology, ecology, distribution, and differentiation

Gymnocolea borealis is reported for the first time for Asia from Russia based on the morphological and subsequent molecular-genetic comparison of rbcL cpDNA sequence of the specimen from the Gydansky Peninsula, West Siberian Arctic. An extended morphological description, generalizing the species characters throughout its range, and data on its variation, differentiation and ecology, and photomicrographs are provided. The occurrence of G. borealis growing as separate shoots among dense mire vegetation makes it easy to overlook. Presently known isolated records of G. borealis support its disjunctive circumpolar distribution.