Tubanova, D.Ya., O.D. Tumurova & E.A. Ignatova. On Dicranum elongatum and D. groenlandicum in Russia
Arctoa (2016) 25: 285–300
Distinction between Dicranum elongatum and D. groenlandicum was tested with molecular markers. Molecular phylogenetic analysis of nuclear ITS1-2 and chloroplast trnL-F sequences confirmed separate status of these species. The importance of width of costa for their delimitation was confirmed; however, cell length in distal and proximal parts of leaves appeared to be variable in both species. Leaf apex in D. groenlandicum is occasionally acute and margins are denticulate near apex in some specimens, contrary to the statement in most handbooks that they are invariably entire and that leaf apex is always obtuse. Dicranum elongatum and D. groenlandicum have similar distribution in Russia. They occur in northern provinces of European Russia and Urals, are known by few records in the Caucasus and are widely distributed in Asian Russia, from Arctic regions to Southern Siberia.