Ignatova, E.A., O.I. Kuznetsova, V.E. Fedosov & M.S. Ignatov. On the genus
Hedwigia (Hedwigiaceae,
Bryophyta) in Russia
Arctoa (2016) 25: 241–277
doi: 10.15298/arctoa.25.20
An integrative molecular and morphological
study of the genus Hedwigia
in Russia revealed at least
five distinct species in its
territory. Hedwigia
czernyadjevae sp. nov. appears to
have a wide
distribution in Transbaikalia, Yakutia and high mountains
of the Russian
Far East, although it never
occurs frequently. Previously its specimens were identified as H. stellata, but straight leaf apices,
strongly incrassate and porose laminal
cells and hairy calyptrae differentiate H. czernyadjevae
from this species, in addition
to sequence data, which place
the Siberian species closer to American H. detonsa. Hedwigia nemoralis sp. nov. occurs in
southern regions of Russia, from
the Caucasus to the Russian
Far East, with one locality
in Central European Russia. It was also
revealed from eastern North America.
It is characterized
by a small plant size, shortly
acuminate, secund leaves with short,
denticulate hyaline hair points and
weakly ciliate perichaetial leaves. Hedwigia mollis sp. nov. has
shortly recurved leaf margins, weakly
sinuose laminal cells and spores
20–25(–28) mm. It was revealed in
European Russia, from the southern
Murmansk Province and Karelia to
the Caucasus, and from South
Urals and Altai Mts. Hedwigia
ciliata is infrequent in Russia,
occurring mainly in the North-Western
European Russia, with few localities
in its central
part. It is characterized by longly recurved leaf margins, sinuose
laminal cells and spores (27.5–)30–35(37.5) mm. Numerous collections in herbaria from the
Caucasus and Asian Russia are
referred to H. emodica, which turned out to
be rather uniform by morphology. In addition to
long hyaline leaf apices, it
is characterized by straight leaves, almost plane leaf
margins and dense papillae with thick, obtuse
branches. Descriptions and illustrations for all five
species of the genus revealed
in Russia, as well as
a key to
the identification of Hedwigia species in Russia
are provided. Four of these
species received a high support
in the molecular
phylogenetic analysis based on chloroplast
trnL-F, mitochondrial
nad5 and nuclear ITS1-2 sequences, while H. emodica was found in an
unresolved grade. Some collections require further studies, and this
first attempt to estimate the
species diversity of Hedwigia in Russia highlights
the complicated problems, likely caused by hybridization between closely related species.