The Lovozero Mountains are one of the largest mountain ranges in the Murmansk Region, characterized by a high level of botanical diversity as well as sozological significance. Based on the specimens of herbarium of the Polar-Alpine Botanical Garden-Institute (KPABG), collected in the Lovozero Mountains, 32 out of 37 protected species recorded in literature were identified. The whole information from the herbarium labels was digitalized, geo-referencing was performed according to a standardized protocol. The article shows that herbarium collections are distributed fairly evenly in the Lovozero Mountains, in contrast to the Khibiny Mountains. Regarding protected areas, the most representative herbarium specimens are from the Seydyavvr Nature Reserve, as well as from the area of the botanical natural monument 'Arnica Plants and Poppies in the Indichjok Gorge'. A considerable proportion of protected species habitats is located outside the existing protected areas, which confirms the necessity to reorganize the Seydyavvr State Nature Reserve into the Seydyavvr Nature Parkand increase its area. A high concentration of protected species, confirmed by herbarium specimens, is associated with the north-western part of the mountain range on Karnasurt Mountain near the Lovozersky Mining and Processing Plant. The spatial analysis revealed the necessity of special botanical research of the protected areas in the Lovozero Mountains, as well as a detailed study of the previous records, especially in the areas of active economic and recreational activities.

As a result of studies of the genus Dactylorhiza undertaken by Alexey B. Shipunov, numerous "northern tetraploids" – plants combining the genomes of diploid D. fuchsii and tetraploid D. maculata s.str., were found among the material from North European Russia. However, it remained unclear whether non-hybrid D. fuchsii was represented in the northern part of the genus' range, as well as what the morphological distinctive features of plants with different ploidy levels were. Cariology and morphometric studies on material from the Murmansk Region showed that both diploid (2n=40) and tetraploid (2n=80) plants occur here, and plants with different ploidy, as a rule, do not occur together. Diploids were associated with D. fuchsii, but their high morphological similarity with tetraploids was noted, apparently due to the smoothing of morphological differences in "northern tetraploids", as well as due to the weak ecological divergence of species of the genus Dactylorhiza in the northern part of their range. The best distinguishing features of plants with different ploidy, established by methods of mathematical statistics, are considered in detail in the paper.

Data on 124 findings of 25 regionally red-listed species of vascular plants collected in the Tersky and Lovozersky Districts of Murmansk Region in areas with Pomor settlements and in Pomor fishing grounds are reported. The surveys covered the abandoned villages of Porya Guba and Kuzreka, villages Kashkarantsy, Chavanga and Sosnovka, as well as areas along the Umba-Varzuga road between Creeks Ludoshny and Kashkarantsky, seacoast stretch from Tochilennyi Creek area to Lodochnyi Creek, from Krivoy Creek area to the Rombach River and from the Pulonga River to Krasnyi Nos Cape near the mouth of the Ponoy River. New localities were detected for 8 very rare species: Armeria scabra, Carex recta, Comastoma tenellum, Cotoneaster antoninae, Cotoneaster laxiflorus, Dactylorhiza incarnata, Pilosella erratica, and Helianthemum arcticum . The latter was found in the region for the second time. Seven species were registered within the boundaries of the nature monument Ametisty mysa Korabl': Cotoneaster antoninae, C. cinnabarinus, C. laxiflorus, Dianthus arenarius, Pilosella erratica, Sedum acre , and Thymus subarcticus.

The Rybachy and the Sredny Peninsulas are the northernmost part of Murmansk Region in the European part of Russia. While the most part of the Region is covered by boreal forest, the Peninsulas are covered by tundra. The vegetation and flora of Murmansk Region are well studied at present. The Peninsulas were first studied in 1829 by a Finnish botanist Jacob Fellman. The most comprehensive research was conducted in the late 19th - early 20th century. Nevertheless, the species composition of the Peninsulas' flora has changed significantly over the past 100 years due to land use and climate change. The aim of this dataset is to make the data on species occurrences for this territory digitally available via GBIF. To date, more or less complete digital floristic data were provided only by the project for digitising the book "Flora of Murmansk Region" (1953–1966).The present dataset is a part of the project studying the vegetation of the territory. We recorded the information about species frequency and distribution using the relevé method.We present a dataset based on 991 relevés from all vegetation types, which includes 16,289 records of georeferenced plant occurrences that belong to 568 species. There are 23 species of lichens (Ascomycota), 142 species of mosses (Bryophyta), three species of liverworts (Marchantiophyta) and 400 species of vascular plants (Tracheophyta) in the present dataset. The taxonomic diversity and unevenness result from the vegetation sampling. The data were collected in 2008, 2009, 2011, 2014 and 2015. The dataset cannot be considered as a complete vegetation database or a flora checklist, but it contains the occurrences and frequencies of the species from all the vegetation types.

Studies of vascular plants and vegetation of the Green Belt of Fennoscandia within Murmansk Region from the beginning of the 19th century until present are reviewed and summarized. Special attention is given to the analysis of the floristic knowledge on existing protected areas in the Green Belt of Fennoscandia, such as the Pasvik Strict Nature Reserve and Ainovi Islands in the Kandalakshsky Strict Nature Reserve, Nature Parks “Rybachy and Sredny Peninsulas” and “Korablekk”, regional nature reserves (zakaznik) “Kutsa” and “Kaita”, nature monuments “Waterfall on the Shuonijok River”, “Bio-group of Spruce Trees at the Range Limit”, “Siberian Stone Pine in the Nickel Forestry District”, as well as planned protected areas: federal and regional nature reserves “Voriema”, “Ionn Nyugoayv” and “Pazovsky”, and nature monument “Mires at Lake Alla-Akkayarvi”. For these territories, the floristic diversity has been analyzed, and data on the number of native and alien species, as well as on the vascular plants of highest nature conservation significance are presented. New records of vascular plants gathered over the past few years from the Murmansk part of the Green Belt of Fennoscandia are reported.

The diversity and distribution of rare and threatened fungi, lichens, mosses, liverworts and vascular plants listed in the Red Data Books of the Murmansk Region (regionally red-listed) and Russia (nationally red-listed) within the Murmansk part of the Green Belt of Fennoscandia (GBF) are discussed. Records include 261 regionally red-listed species (8 species of fungi, 57 lichens, 31 liverworts, 55 mosses, and 110 vascular plants), i. e. 63.5 % of the total pool of red-listed species, and 17 nationally red-listed species (4 lichens, 5 liverworts, 1 moss and 7 vascular plants). Protected areas harbor 17 of the 30 nationally red-listed species known from the Murmansk Region, and 219 of the 411 regionally red-listed species, proving that protected areas inside GBF play an essential role in nature conservation in the Murmansk Region. The protected areas of greatest conservation significance for a majority of the analyzed groups are the Kutsa Nature Reserve (Zakaznik), Pasvik Stat Nature Reserve and Poluostrova Rybachy and Sredny Nature Park. For 43 red-listed species there are no records from protected areas inside GBF, including such species rare in the Murmansk Region as Peltigera lyngei, Carexatherodes, Botrychium lanceolatum, Lomatogonium rotatum, Draba nivalis, D. lactea, Flaviporus ci-trinellus, Skeletocutis lilacina, Chaenothecopsis fennica, Frullania tamarisci, Scapania simmonsii, Rhabdoweisia fugax, Tortula mucronifolia, Tanacetum bipinnatum, etc.). The priority steps to be taken to secure the preservation of rare and vulnerable species populations are reorganization of the Kutsa Nature Reserve into a Nature Park and alteration of the boundaries of the Poluostrova Rybachy and Sredny Nature Park.

The results of surveys for rare and red-listed plant species on the north-eastern coast of the Kola Peninsula at Drozdovka and Ivanovskaya Bays (Barents Sea, Murmansk Region) are presented. Data are provided on newly found locations of red-listed species in the Murmansk Region: two mosses (Buxbaumia aphylla Hedw., Rhabdoweisia fugax (Hedw.) Bruch et al.), four liverworts (Anastrophyllum sphenoloboides R. M. Schust., Haplomitrium hookeri (Sm.) Nees, Metzgeria furcata (L.) Dumort., Prasanthus suecicus (Gottsche) Lindb.), 13 species of vascular plants (Arctanthemum hultenii (A. Love & D. Love) Tzvelev, Arnica fennoskandica Jurtzev & Korobkov, Carex glacialis Mackenz., C. recta Boot., Draba fladnizensis Wulf., D. norvegica Gunn., Gentianopsis dentosa (Rottb.) Ma, Isoetes echinospora Durieu, I. lacustris L., Phippsia algida (Sol.) R. Br., Rhodiola rosea L., Salix nummularia Anderss., Trisetum spicatum (L.) K. Richt.), and 21 other rare plant species. We recommend establishing a regional-level nature monument in the lower reaches of the Drozdovka River, where a high diversity of plants and many rare species were revealed.