Metacalypogeia cordifolia is recorded for the first time for the Republic of Sakha (Yakutia) from the Udokan Range. The species was found in the shaded narrow with nearly vertical walls gorge, about 1.5 m wide and 2–3 m high, that accumulates snow, covering the plants in winter and has a seepage, watering the plants in summer. It is the northernmost mainland record of M. cordifolia. The identification is confirmed by obtained complete trnL-F cpDNA sequences corresponding to available sequences of M. cordifolia from the Russian Far East and Japan. The description of collected plants, their photomicrographs, and data on morphological variation, ecology, and distribution of M. cordifolia are provided. The key to distinguish M. cordifolia from morphologically similar northern taxa is presented. Differentiation of the genus from morphologically similar representatives of the genera Bazzania, Eocalypogeia, Calypogeia, Mnioloma, and Protocalypogeia is discussed. A joint analysis of bioclimatic data and habitat conditions, along with the absence of traces of glaciation at the place of gathering the species, indicate that it is a refugium. Metacalypogeia cordifolia in the Udokan Range appears to be an Eopleistocene relic.

The Sette-Daban Range, about 650 km long, is the southernmost part of theVerkhoyansk Mountains System. The only information on the liverworts of the range so far has been based on the results of field research 2000–2001. The bedrock of the Sette-Daban Range consists mainly of limestone and dolomites, while the rest of the Verkhoyansk Mountains System is composed of acid rocks. Because of this, the flora of the liverworts of the Sette-Daban Range differs significantly in its species. The present research was carried out in 2015–2017 in the basins of the Vostochnaya Handyga and Sakkyryr rivers using the route method in different habitats throughout the vertical profile. The annotated list describes the growth conditions of each species and indicates the structures associated with reproduction. A total of 44 species were identified. Of these, Apopellia alpicola and A. megaspora are new for Yakutia, 22 species are new to the flora of the Sette-Daban Range, seven species are rare in the territory of Yakutia or in the mountains of the northeast of the republic (Arnellia fennica, Eocalypogeia schusteriana, Frullania subarctica, Lejeunea alaskana, Mannia triandra, Sauteria alpina, Scapania sphaerifera). Eocalypogeia schusteriana, Mannia triandra, and Scapania sphaerifera are included in List of Russian Protected Species, Lejeunea alaskana — in the Red Data Book of the Republic of Sakha (Yakutia). At present, 69 species are known for the liverwort flora of the Sette-Daban Range. Sette-Daban is the habitat and conservation area of many basiphilic and calcephilic liverworts, rarely found in the Verkhoyansk and Chersk Mountain systems.

A motley grass steppe site with an area of 25 hectares was investigated on a slope of the right bedrock coast of the Ina River, a left tributary of the Barguzin River in Buryatia. An assemblage of the heteropterans in the area was found to consist of only 30, and that of the weevils, of 16 species. The host plant to weevil species ratio at this site near the northeastern boundary of the steppe zone is about 6 : 1, i.e., fourfold that in the plain part of Stavropol Territory close to the western boundary of the steppe zone in its most diverse although least preserved part. Two new wingless species of weevils with apparently very narrow ranges, probably restricted to the Barguzinskaya Depression, are described—Phyllobius (Angarophyllobius) sofronovorum Korotyaev, sp. n. and Stephanocleonus (Stephanocleonus) lysovi Korotyaev, sp. n.

In the summer of 2023, a true bug Arocatus rufipes Stål, 1872 was detected on the European white elm in Irkutsk, which does not occur in natural environment in Siberia and is used for landscaping urban areas. The western boundary of the natural range of this Asian Heteroptera species runs in Buryatia. Currently, the species is probably spreading west of the Lake Baikal due to urban plantings using trees of the genus Ulmus.

The seasonal patterns of changes in the content of lipophilic antioxidants β-carotene (β-Car), zeaxanthin (Zx), α-tocopherol (α-Toc), plastoquinone (PQ)/plastoquinol (PQH2) were studied in the assimilating shoots of evergreen shrub Ephedra monosperma J.G. Gmel ex C.A. Mey under natural conditions of Central Yakutia. The shortening of the photoperiod and the seasonal decrease in temperature induced a 1.4-fold increase in α-Toc content. The fall in the average daily temperature from 0.1 to -8.1°C in October led to a decrease in the content of β-Car as a result of the accumulation of rhodoxanthin (Rhd). In this period a sharp increase in the content of Zx retained overnight was also detected. In winter, elevated content of Zx and α-Toc persisted. During September, the content of PQH2 increased by 2.5 times and PQ by 1.4 times (compared to July). The beginning of exposure to freezing average daily temperatures from -3 to -5°C led to the depletion of the total PQ pool by 18%. However, the content of PQtot in the winter months was 1.5 times higher than at the end of July. The results revealed different timing and temperature ranges of variation for individual antioxidants during the development of frost resistance in ephedra.

This article presents an annotated list of plant type specimens stored in the Herbarium of the IBPC SB RAS (SASY), which is one of the largest in northeast Russia. The Herbarium fund is represented by five departments (vascular plants, mosses, lichens, aphylophore fungi, and algae), where about 95000 herbarium samples are stored exluding algae tests. The Herbarium has a collection of plants from Western and Eastern Siberia, the Far East, and some central regions of Russia. The exchange fund contains more than 3000 species of plants. Typical samples stored in Herbaria are of a particular value. In total, 14 species and 2 subspecies of liverworts, mosses, and vascular plants from 11 families were isolated from the main collection of the SASY Herbarium, which are represented by 14 types, 16 isotypes, 14 paratypes, and 5 epitypes (Frullania ignatovii Sofronova, Mamontov et Potemkin, Barbula jacutica Ignatova, Grimmia jacutica Ignatova, Bednarek-Ochyra, Afonina, J. Muñoz, Aconogonon amgense (V. Mich. et V. Perf.) Tzvel., Androsace gorodkovii Ovcz. et Karav., Anoplocaryum elenae Volot., Artemisia karavajevii Leonova, Astragalus zhiganicus L. Kuzn., and Castilleja galaсtionovae E.G. Nikolin, Castilleja rubra (Drob.) Rebr. var. multicaulis E.G. Nikolin, Castilleja tenella Rebr., Oxytropis scheludjakovae Karav. et Jurtzev, Rosa acicularis Lindl. subsp. melanocarpa L. Kuzn., Sorbocotoneaster pozdnjakovii Pojark. var. cotoneaster L. Kuzn. et Volot., S. pozdnjakovii Pojark. var. sorbus L. Kuzn. et Volot., Salix x zhataica Efimova, Shurduk & Ahti). Plants, the types of which are stored in SASY, represent the indigenous flora of Yakutia and are found quite rarely in this territory; eight of these species are listed in the Red Book of the Republic of Sakha (Yakutia), and 11 species are endemic. For each sample, a quote of the original label is indicated, and a brief ecology, distribution, and rarity category is given. The originality of the publication of each standard sample is indicated by the images of digitized herbarium sheets and their labels.

The paper provides an annotated list of true bugs (Heteroptera) of the Tunkinsky National Park. The list is based on the results of collections made in 2015 and 2019. With the author's data and literature data combined, the list contains 63 species of true bugs from 48 genera and 12 families. For the first time, 54 species of Heteroptera were identified in the Tunkinsky National Park. Two of the species — Acalypta platycheila (Fieber, 1844) and Eurydema ventralis Kolenati, 1846 — are new to the fauna of the Republic of Buryatia. The species E. ventralis is reported for the first time for Baikal Siberia. The study area is likely to be the eastern limit of their distribution.

СОВРЕМЕННОЕ СОСТОЯНИЕ ПРИРОДНЫХ КОМПЛЕКСОВ ЭКОПАРКА «ОЗЁРА НА СНЕЖНОЙ» (ХРЕБЕТ ХАМАР-ДАБАН, ЮЖНОЕ ПРИБАЙКАЛЬЕ)1,2 Софронов А.П., 1 Софронова Е.В.1 ФГБУН «Институт географии им.В.Б.Сочавы СО РАН», Иркутск, e-mail:

Siberia is a current research area with a relatively well-preserved natural environment, indigenous structures of geosystems, but also with a high number of anthropogenic disturbances and great prospects for economic development of natural resources. Long history of development of modern landscapes in Siberia has left its footprint in the composition of modern natural complexes. Siberia is the result of a unique combination of natural-geographical, historical, and socio-economic factors. The results of human activity impact on the environment constitute the main factor in the formation of modern landscape structure of Siberia. The consequences of the 400-year period of intensive economic development of the natural-resource potential (since the arrival of Russian population to the region) are manifested in the dynamics of geosystems, expressed in the replacement of natural state complexes with the transformed complexes.

The study of vegetation stability remains an important and poorly developed issue of geobotany. Results from studying of a study of resistance to the pyrogenic factor of plant communities of vegetation cover of the North Baikal and Upper Angara depressions are presented. In recent years, fires have become catastrophic in Siberia, as well as on the territory of the country as a whole; therefore, pyrogenic impact is one of the main negative anthropogenic factors. We suggest an original technique for determining the parameters of vegetation resistance to the pyrogenic factor, based on assessing ignitability. The susceptibility to fire of both individual plant species and plant layers of cenoses, as well as the degree of damage by fires, have been comprehensively studied, with regard for the mesoclimatic conditions and areal distribution throughout the territory. It was established that the resistance of the communities can vary according to on their hierarchical rank. As a result of this research, a legend and a medium-scale map of the vegetation resistance in the region to the pyrogenic factor have been generated. It was revealed that the most stable communities are sparse alpine tundras, alpine meadows and meadow-swamp communities of the Upper Angara floodplain and wet forests of mountain valleys. The medium-stable cenoses include tundra watersheds and sloping summits with well-developed shrub-lichen cover, sparse communities of Pinus pumila, small-leaved forests, steppe slopes and forest communities of the floodplain. The lowest degree of stability is typical for closed P. pumila thickets, subgoletz dark coniferous-larch forests, and mountain taiga dark coniferous forests, as well as for pine forests of the submontane-depression belt. One important characteristic of the stability of the communities is the duration of recovery of the primary (conventionally primary) state. It is shown that the accessibility of natural communities to humans significantly affects the resistance of vegetation to the pyrogenic factor, because this greatly increases the likelihood of fire in any of these cenoses.

New data on the Heteroptera fauna of the Japanese elm (Ulmus japonica (Rehder) Sarg.) communities and adjacent habitats in the lower part of the Selenga River valley are provided. The list contains 51 species, 9 of which are newly recorded for Buryatia (Deraeocoris kerzhneri Josifov, 1983, Notostira elongata (Geoffroy, 1785), Gampsocoris culicinus culicinus Seidenstücker, 1948, Drymus sylvaticus (Fabricius, 1775), Trapezonotus anorus (Flor, 1860), Plinthisus pusillus (Scholtz, 1847), Corizus hyoscyami hyoscyami (Linnaeus, 1758), Stictopleurus abutilon (Rossi, 1790), Acanthosoma denticaudum Jakovlev, 1880). The distribution of several rare or poorly known species in Baikal Siberia is specified.

A rare bug species Acanthosoma denticaudum Jakovlev, 1880 is registered for Baikal Siberia from Irkutskaya Oblast for the first time.