The presented work is based on the study of material collected by F.A. Romanyuk on Matua Island, Middle Kurils, in 2017, and on literature data. Currently, 70 lichen species are registered for the island; among them 24 are known only from literature data and 66 were collected during our study including 46 species registered for Matua for the first time. Verrucaria fusconigrescens is the first record for the Russian Far East. Lecanora atrosulphurea, L. sulphurea, Lecidella asema, Lendemeriella kamczatica and Lepra panyrga are new to Kurils and the Sakhalin Region. Information about location and substrate is provided for each species. For the species new to the Sakhalin Region, brief information on ecology and distribution, as well as images are provided.

The genus Anthracothecium is re-reported for the territory of Russia. The article discusses that A. speciosum f. speciosum was mistakenly included in the lists of lichens of Russia, of the south of the Far East and of Shikotan Isl., and also that A. speciosum f. iturupiense morphologically and anatomically corresponds more closely to the genus Pyrenula. Thus, the tropical genus Anthracothecium is represented in Russia by one species, Anthracothecium australiense reported here to the Kunashir Island. This is a first record of the species in Russia which has previously been known to Australia, Oceania (New Guinea), Asia (Japan and China), North and South America (Brazil, Argentina). The species is characterized by large, brown muriform ascospores with thin walls, as well as immersed, erumpent, and semi-immersed, black, globose perithecioid ascomata (0.5–)0.7–1.0 mm wide with a short neck and lateral ostiole. The data on distribution, ecology, and distinctive features of the species as well as photos are provided.

As a result of a revision of the lichen genus Thelotrema in the Sakhalin Region (Russian Far East), two species are reported as new to the region. Thelotrema diplotrema is recorded for the first time in Russia, and T. suecicum is reported for the first time in Asia. T. diplotrema previously known only from evergreen forests in tropical and subtropical regions of Africa, Australia, and Asia, was found in an old-growth forest with bamboo understory on the bark of deciduous trees on Kunashir Island. This finding represents the northernmost locality of the species in the temperate zone. T. suecicum, a widespread lichen of rainforests and wet montane forests in the cool-temperate zones of the Northern and Southern Hemispheres (Europe, North and South America, Australia, and New Zealand), was collected in a warm, humid riparian forest on the bark of Alnus hirsuta in southern Sakhalin Island and in an oak forest on the bark of Quercus crispula on Iturup Island. Following this revision, three species of Thelotrema are confirmed for the Sakhalin Region, including the previously known T. lepadinum. Detailed morphological, anatomical, and ecological descriptions are provided, along with illustrations, diagnostic features of similar species, and an identification key for the species of Thelotrema and morphologically related taxa occurring in the region.

The current study is a continue of the series “New records and noteworthy lichen species from Sakhalin and Kurils, Far East of Russia”. The previous work contained information on 9 lichens new to the territory. This work contain 11 new lichen records from Sakhalin and Kurils, including Anisomeridium viridescens – the first report in Asia and Russia and pantropical species Agonimia pacifica – a new record for Russia. Buellia leptocline, Rinodina laevigata and Rhizocarpon polycarpum found on Sakhalin are the first reports for the south of the Russian Far East. Julella sericea found on Sakhalin is the first report for the Sakhalin Region. Swinscowia stigmatella found on Iturup and Kunashir is the first report for Kurils. Arthothelium spectabile is a new record to Shikotan. Collema flaccidum, C. furfuraceum and C. japonicum are new records to Iturup. For noteworthy species, information on distribution, ecology and distinctive features of similar species, and photos are provided.

Nine new records of lichens from Sakhalin and Kurils are presented including Caloplaca monacensis – new to the Russian Far East, Phaeophyscia constipata and Rostania ceranisca – new to the south of the Russian Far East, Massalongia cornosa and Mycoblastus alpinus – new to the Sakhalin Region, Heterodermia diademata – new to Kuriles, Bilimbia tetramera, Fissurina inabensis and Coenogonium pineti – new to Kunashir Island. For noteworthy species, information on distribution, ecology, and diagnostic traits of similar species is provided. Most of all reported species, namely Bilimbia tetramera, Caloplaca monacensis, Massalongia cornosa, Mycoblastus alpinus, Phaeophyscia constipata and Rostania ceranisca, are considered to be rare in the region.

The organization of the lichen herbarium in the Institute of Marine Geology and Geophysics of the FEB RAS was initiated in 2014 after a number of integrated expeditions in the Sakhalin Region. The herbarium is based on the collections of Aleksander K. Ezhkin and Vladimir V. Kaganov. A significant amount of lichen samples was collected in protected areas of the Sakhalin Region, in wild remote sites, and in areas of volcanic activity. Currently, a part of the collection (1178 samples, 307 species) is mounted and stored in the Laboratory of plant ecology and geoecology, which is about 1/8 of all herbarium material of lichens stored in the Institute of Marine Geology and Geophysics of the FEB RAS.

The paper presents an annotated list of lichens of the eastern slope of Berutarube volcano, one of the most inaccessible and poorly studied active volcanoes on Iturup Island. Samples of lichens were collected in August 2023 from eroded areas in the summit part of the volcano, as well as on the eastern slope along the Andrey Creek, in the upper reaches of which unnamed cold acidic springs discharge. In total, 53 species of lichens were identified from the sampling sites, of which 20 species were new to Iturup Island, 2 species were new to the Kuril Islands, and 1 species was new to the Sakhalin region. In the summit part of the volcano, lichens typical for areas of volcanic activity were identified: Cladonia crispata, Cladonia straminea, Huea confluens, Lecidea plana, Melanelia stygia, Pseudephebe pubescens, Rhizocarpon badioatrum, and Umbilicaria torrefacta. The influence of the solfataric gases of the volcano on the lichen biota of the Andrey Creek valley has not been revealed, which allows us to make the assumption that there is no direct influence of the products of the solfataric activity of Berutarube volcano on the natural environment of its eastern slopes.

The paper presents the classification results for moss and lichen communities (synusiae) on the bark of living trees Populus suaveolens Fisch. in the southern part of Sakhalin Isl. The P. suaveolens was selected for study as a phorophyte species due to large trunk size and the high species diversity of epiphytes (Kaganov, Koroteeva, 2022), which provided the basis to trace the gradient of man impact since poplars are being actively used in settlement greening as well grow in natural riparian forests (Korznikov, Popova, 2018). Due to wide range of P. suaveolens our study opens perspectives for syntaxonomic generalizations in broader geographical comparison. We sampled 110 relevés (0.16 m2, each consisting of a set of 4 vertical rectangle subplots 0.1×0.4 m faced to north, east, south, and west on a single tree) in urban parks and gardening, artificial forest stands on the periphery of an urbane zone, and natural riparian forests. The modified TWINSPAN algorithm (Roleček et al., 2009) from the JUICE 7.1.101 (Tichý, 2002) was used for relevé sorting. New syntaxa (Braun-Blanquet approach) were described based on TWINSPAN clustering according to the 4th edition of the International Code of Phytosociological Nomenclature (Theurillat et al., 2021). Lecanoro pachycheilae–Collemetum furfuracei ass. nov. Holotypus: relevé 19 in Table 1; 27.10.2017; 46.9675° N 142.80194° E; natural riparian forest in the valley of the Rogatka River, V. V. Kaganov, A. K. Ezhkin. Diagnostic combination: Bacidia sachalinensis, Buellia disciformis, B. erubescens, Caloplaca tarani, Collema furfuraceum, Eopyrenula intermedia, Heterodermia speciosa, Kurokawia isidiata, Lecanora allophana, L. pachycheila, Lecanora sp., Lepra amara, Lepraria incana, Leptogium burnetiae, L. cyanescens, Mikhtomia gordejevii, Opeltia flavorubescens, Pertusaria pertusa, Pylaisia condensata. Ecology: subnitrophilous communities of mosses and lichens on Populus suaveolens bark in natural riparian forests or semi-natural forest stands. Geographic distribution: southern part of Sakhalin Isl. Lecanoro pachycheilae–Collemetum furfuracei typicum subass. nov. Holotypus: relevé 19 in Table 1. Diagnostic combination: correspond with the association. Ecology: subnitrophilous communities of mosses and lichens on Populus suaveolens bark in natural riparian forests. Geographic distribution: correspond with the association. Lecanoro pachycheilae–Collemetum furfuracei inops subass. nov. Holotypus: relevé 12 in Table 1; 17.11.2017; 47.02944° N 142.72194° E, forest stand in the riparian zone of the Rive Krasnoselskaya, urban zone of the Yuzhno-Sakhalinsk city, V. V. Kaganov, A. K. Ezhkin. Diagnostic combination: absent. Ecology: subnitrophilous communities of mosses and lichens on Populus suaveolens in artificial forest plantings on periphery of urban areas. Geographic distribution: correspond with the association. Physciello melanchrae–Candelarietum concoloris ass. nov. Holotypus: relevé 4 in Table 1; 01.10.2017; 46.93333° N 142.73333° E, Yuzhno-Sakhalinsk city, park area, V. V. Kaganov, A. K. Ezhkin. Diagnostic combination: Candelaria concolor, Leskea polycarpa, Physciella melanchra. Ecology: nitrophilous communities of mosses and lichens on Populus suaveolens bark in urban gardening. Geographic distribution: settlements in the southern part of Sakhalin Isl. Physconio detersae–Phaeophyscion hirtuosae all. nov. Holotypus: ass. Lecanoro pachycheilae–Collemetum furfuracei; this paper. Diagnostic combination: Lewinskya sordidum, Mikhtomia gordejevii, Phaeophyscia hirtuosa, Physconia detersa, P. grumosa, P. kurokawae, Pylaisia condensata, P. polyantha. Ecology: nitrophilous epiphyte communities and semi-nitrophilous epiphyte communities of mosses and lichens on tree bark in natural riparian forests, artificial plantings, and urban gardening. Geographic distribution: southern part of Sakhalin Isl. The new alliance is placed into the order Physcietalia Hadač in Klika et Hadač 1944 of the class Physcietea Tomaselli et De Micheli 1952 (Mucina et al., 2016): The classification solutions proposed are well suited to the change in the composition of epiphytic communities on the gradient of the man impact increasing, from the natural habitats of Populus suaveolens in riparian forests to artificial plantings in the urban environment. Ass. Physciello melanchrae–Candelarietum concoloris unites epiphyte communities in the urban artificial plantings (parks, squares, alleys, street, yard landscaping) while the ass. Lecanoro pachycheilae–Collemetum furfuraecei does this outside of urbanized areas. The distribution of the subass. L. p.–C. f. typicum is limited to natural forests and the subass. L. p.–C. f. inops to semi-natural habitats — large forest parks or artificial forest plantings on the urbanized area periphery.

Frullania hamatiloba is recorded for the first time for Russia from Sakhalin.It is a northernmost locality for this species, for which was previously known from Japan (Hokkaido, Honshu, Shikoku, and Kyushu), Taiwan, China (Anhui, Guangdong) and the Korean Peninsula.The species is distinguished by (1) relatively large, shallowly bilobed (up to 0.26 the length) underleaves with obtuse to acute lobes and mostly angulate sinus, (2) characteristic leaf lobules which are transversely to longitudinally elongated (when well-developed), with incurved rostral portion, and (3) tuberculate perianth with three keels.Description and photomicrographs of F. hamatiloba from Sakhalin are provided together with discussion on its ecology and differentiation from having much in common F. fauriana, F. kagoshimensis, F. pedicellata, F. taradakensis and F. usamiensis. РезюмеНовый для России вид печеночников Frullania hamatiloba выявлен на Сахалине.Это наиболее северная находка данного вида, который ранее был известен только в Японии (Хоккайдо, Хонсю, Сикоку и Кюсю), на Тайване, в Китае (провинции Аньхой, Гуандун) и в Республике Корея.Для F. hamatiloba характерна следующая комбинация признаков: (1) амфигастрии крупные, неглубоко (до 0.26 длины) двулопастные, в основном с угловатой вырезкой и тупыми или заостренных лопастями, в нижней половине часто с сильно отвороченными краями; (2) брюшные лопасти от продольно до поперечно удлинённых, в основном с изогнутой и вытянутой вниз ростральной областью; (3) периантий с тремя выступающими килями и бородавчатой до пластинчатой поверхностью.Приводятся описание и микрофотографии F. hamatiloba, а также обсуждение экологии, вариабельности и отличий этого вида от морфологически сходных видов F. fauriana, F. kagoshimensis, F. pedicellata и F. usamiensis.

The paper presents data on six lichen species new to Sakhalin Island. Two of them, namely Physconia subpulverulenta and Bacidia elongata, are recorded for the Sakhalin Region for the first time. Mycobilimbia carneoalbida, Mycobilimbia tetramera, Chaenotheca xyloxena, and Pseudoschismatomma rufescens are noted for Sakhalin Island for the first time. Brief information on distribution, ecology, distinctive characters and illustrations are provided for the species.

Two new records of Pannariaceae lichens – Fuscopannaria mediterranea and F. sorediata were registered for the Russian Far East using DNA and morphological investigation of the samples collected from the Sakhalin and Kuril Islands. Both species are morphologically problematic to distinguish from other sorediate species of the genus Fuscopannaria. Fuscopannaria mediterranea is reported for the first time to East Asia supported by the ITS nrDNA molecular-phylogenetic data. After investigation of the material from Sakhalin and Kuriles we excluded Fuscopannaria confusa and F. leprosa from the species list of the Russian Far East. The rest controversial material from Sakhalin and Kuriles was identified as F. alhneri as the most common species of the genus in the region.

The presented work is based on the study of material collected by F.A. Romanyuk in the surroundings of Sarychev Peak active volcano on Matua Island, middle Kurils in 2017. Two families – Physciaceae and Caliciaceae – were sorted out from the collection and studied at first. As a result, seven species of the families were found: two species of the genus Rinodina, two species of the genus Physcia, two species of the genus Buellia and the species Tetramelas chloroleucus. All found species of the studied families were first identified for Matua Island. Matua Island is the northernmost location point in Eurasia for the species Rinodina ascociscana. Buellia badia is a new registered species for the Sakhalin Region.

As a result of identification the moss collections from Shikotan, Kunashir, Iturup and Urup islands (Southern Kuril Islands, Russian Far East) collected by T.I. Koroteeva, V.E. Fedosov, A.V. Shkurko, N.S. Liksakova, and A.K. Ezhkin in 2015–2021, new species for the islands were revealed: 6 ones for Urup, 8 for Iturup, 10 for Kunashir, and 19 for Shikotan. For the first time, 4 species new for the Kuril Islands were discovered, including three new for the Sakhalin Region (Forsstroemia cryphaeoides, Haplocladium intermedium, Rhizogemma staphylina, Meteorium buchananii). Another 3 species found in the islands are new for the Southern Kuriles (Dicranum fragilfolium, Gollania turgens, Hygroamblystegium varium). Most of the discovered species are rare in both the Sakhalin Region and the Russian Far East. To date, the moss flora of the Southern Kurils numbers 468 species and is the richest bryoflora in Russia.

We received a unique material on the natural environment development for the last 12 400 cal. yr. BP in the central part of Iturup Island. The high-resolution paleoreconstructions were based on multi-proxy study of the paleolake sediments found on the plateau (height 400–420 m) located northwest of the Baransky Volcano. For the first time, a record of paleogeographic events was obtained for the Late Glacial and the early Holocene. The age model is based on 9 radiocarbon dates. Diatom analysis allowed us to distinguish 11 stages of lake-swamp evolution. The paleolake reached its maximum depth at ~9 890–7 900 cal. yr. BP and became extinct at 1 400 cal. yr. BP. The stages of vegetation development and the factors determining the change of landscapes have been restored. The Younger Dryas cooling recorded in Iturup was characterized by humidity changes. The role of forest vegetation abruptly increased at the Pleistocene-Holocene boundary of ~11 470 cal. yr. BP) under warmer climatic conditions. Distribution of shrub pine as an indicator of stable snow cover was analyzed. Dark-coniferous forests existed in the mountainous part of the island since the Late Glacial and were most widely developed in the early Holocene. The onset of birch forest expansion at 6 200 cal. yr. BP was associated with the intensification of volcanic activity and frequent ash falls. A number of cold events were identified, whose manifestations were enhanced by the weakening of the Soya warm current. The intensive transfer of allochthonous pollen from the southern Kuril Islands and the Japanese Islands at 3 540 cal. yr. BP is a sign of cyclogenesis intensification in the Kuril Islands. Manifestations of the Holocene climatic rhythms in the landscape development of the Iturup mountainous part, as well as the influence of warm and cold currents and other regional factors, were analyzed.

A new epiphytic species of crustose Teloschistaceae, Coppinsiella extremiorientalis, is described from the floodplain forests of the boreal zone of the Russian Far East. It is characterized by its white to whitish grey, thin to disappearing thallus mostly without anthraquinones, dull orange zeorine pruinose apothecia with an anthraquinones composition corresponding to chemosyndrome A. Phylogeny of the genus Coppinsiella, which was previously unknown in the Far East, is discussed, as well as the morphology, ecology and geographical distribution of Coppinsiella species. A new combination for Caloplaca fiumana, an older name for Coppinsiella orbicularis, is also formally proposed.

The paper presents the results of studying soil lichens in areas of thermal habitats on the Kuril Islands, including the features of lichen distribution on the isles. Totally four species of epigeic lichens were found when studying the thermal fields on Kunashir and Iturup isles: Cladonia graciliformis, C. granulans, C. vulcani, and C. furcata. First three species are closest to active fumaroles and have the highest rates of occurrence frequency for these habitats.

The paper provides data on morphology, ecology, differentiation and distribution of the crustose, epiphytic and epixylic lichen Rinodina sibirica in Eurasia. An anatomical and morphological description of R. sibirica is provided based on 138 specimens studied. Based on these records, we show that the distribution of the species from the Russian Far East is ranging from the Kamchatka Peninsula to the Mongolian border in the south and the Krasnoyarsk Territory and the Tyumen Region in the west. Current data suggest that R. sibirica is an American-Asian species with a wide Amphiberingian range, only slightly extending to Europe in the Ural Mts.

The results of the study of the gross content of 14 chemical elements in lichen Platismatia interrupta collected around the geothermal power station “Mendeleevskaya” on Kunashir Island are presented. The highest exceedance was noted for As in the research area. The gross content of As varies from 0.8–2.6 mg/kg in control areas and up to 5–9 mg/kg in the impact zone, i.e. the maximum excess in lichen is noted by 11.6 times. For other elements, there were no strong exceedances in the impact zone compared to the control areas. According to the results of regression analysis, a statistically reliable inverse exponential relationship between the content of As and the distance to the power station (adjusted R2: 0.86, p-value: 0.001) is traced. The average value of the enrichment coefficient for As exceeds 100, which indicates the non-substrate origin of this element.

The results of research of epiphytic lichens as bioindicators of the atmosphere pollution in Yuzhno-Sakhalinsk city and its suburbs are reported. Populus maximowiczii was chosen as the most common tree species in the plantings of the city as a lichen substrate. Control sites was chosen in natural habitats of Populus maximowiczii in surroundings of the city. In total, 47 lichen species were registered on bark of Populus maximowiczii on all sites. Three clusters of anthropogenic influence on lichens were defined by the results of the cluster analysis of 15 stations where species composition and occurrence frequency were registered. Four groups of lichen sensitivity to anthropogenic influence were identified according to confinement to these three clusters. The analysis of species distribution by the degree of sensitivity was made for each site.