Ignatova, E.A., V.E. Fedosov, A.V. Fedorova, U.N. Spirina & M.S. Ignatov. 2019. On moss family Lembophyllaceae in the Russian Far East

Arctoa (2019) 28: 179–202

doi: 10.15298/arctoa.28.16

An integrative approach to the revision of the Lembophyllaceae in the Russian Far East, including molecular phylogenetic and morphological studies, revealed five species, three of Dolichomitriopsis, including one new species, Dolichomitriopsis cherdantseviae, and one species of Dolichomitra, one new genus Dolichomitriadelphus for the taxon commonly known as Isothecium hakkodense. The species known as Isothecium subdiversiforme is still not found in Russia, so it was analyzed based on Japanese material and also determined to be unrelated to any other species of Lembophyllaceae, thus it is segregated in a genus of its own, Isotheciastrum. The combined analysis of European, Asian and American species shows that the genus Isothecium has mostly Amphiatlantic distribution and combines species of I. alopecuroides affinity. The group of Isothecium myosuroides and related species form a clade sister to Asian Dolichomitra, Dolichomitriopsis, Isotheciastrum, and American Bryolawtonia and Tripterocladium. This fact suggests a resurrection of the genus Pseudisothecium Grout for I. myosuroides, I. stoloniferum, I. interludens, I. prolixum, I. montanum, I. holtii, I. cardotii, and I. cristatum. All species of the family from the Russian Far East are illustrated and the variation of their morphology is discussed.