Ignatov, M.S., E.A. Ignatova & O.I. Kuznetsova.
2021. A rare European endemic
moss genus Arvernella is discovered in Sakhalin, Russian Far East, where it is also rare
Arctoa (2021) 30: 1–7
A molecular phylogenetic
analysis revealed that a tiny Amblystegiaceae plant
from Sakhalin in the Russian Far East is most
closely related to the recently described European endemic genus and species Arvernella microclada.
This species is one of the smallest pleurocarpous
mosses and it remains known only from a limited area in France, 9000 km from Sakhalin.
Sakhalin plant differs from European in longer
leaf costa and almost smooth laminal
cells versus distinctly prorate in A. microclada,
in addition to genetic differences. An equally small East Asian Platydictya fauriei,
known from Japan and Corea, differs from the Sakhalin
plant in its narrow laminal cells (4–6:1 vs.
1.5–2.5:1). Thus, this Sakhalin plant is
described as a new species, Arvernella pisarenkoi Ignatov & Ignatova.