Fedosov V.E. 1,2, Ignatova E.A. 1, Fedorova A.V. 3, Kucera J. 4 2021. Microamblystegium – a new genus of Amblystegiaceae from Shikotan Island (South Kurils, Russian Far East) // Arctoa. Vol. 30: 417–424 [in English].
1 – Lomonosov Moscow State University, Biological Faculty, Geobotany Dept., Leninskie Gory Str. 1-12, Moscow 119991 Russia; e-mails: firstname.lastname@example.org, arctoa@ list.ru. ORCID (VF) 0000-0002-5331-6346, (EI) 0000-0001-6287-5660
2 – Botanical Garden-Institute, FEB RAS, Makovskogo Street, 142, Vladivostok, 690024, Russia
3 – Tsitsin Main Botanical Garden, Russian Academy of Sciences, Botanicheskaya Str., 4, Moscow 127276 Russia; e-mail: email@example.com. ORCID (AF) 0000-0001-7362-2124
4 – Faculty of Science, Department of Botany, University of South Bohemia, České Budějovice, Czech Republic; e-mail: firstname.lastname@example.org. ORCID (JK) 0000-0002-0230-5997
KEYWORDS: Hypnales, molecular phylogeny, cryptic diversity, parallel evolution
ABSTRACT. A molecular phylogenetic study based on the plastid trnL-trnF, atpB-rbcL and nuclear ITS sequences resolved an unnamed tiny saxicolous moss recently collected in Shikotan Island in a clade with Kandaea, Palustriella and Cratoneuron. At the same time, it markedly differs from them morphologically in having homogeneous stem cross section, weak single costa reaching only 0.3 to 0.7 of leaf length, and very weakly differentiated alar cells. The moss is therefore described here as Microamblystegium saxicola gen. et sp. nov. We speculate that it represents another specialized evolutionary lineage with miniaturized and simplified morphology likely associated with adaptation to growth in shaded cliff niches, matching a similar pattern observed in the recently described amblystegiaceous genus Arvernella. Such specialized lineages of minute saxicolous mosses remain poorly known due to their outstanding rarity.