The Atlas of Distribution of Mammals in the European Part of Russia is almost ready and will soon be published. This is the first publication in Russia that summarizes information on the distribution of mammals in the European part of Russia, collected over the entire period of zoological observations in the country. It is the result of many years of joint work by a large group of authors from scientific organizations in different cities of the country and a unique example of the successful involvement of amateur naturalists in scientific research activities. For more information, follow the link.

The guidelines "Diagnostics and prevention of helminthiasis in reindeer in zoos" are addressed primarily to veterinarians, livestock specialists and keepers of those zoos whose collections include reindeer. In addition, these guidelines may be useful to veterinarians and biologists, students and postgraduates of biological, veterinary and agricultural universities, as well as to all those who are not indifferent to the problems of helminthology of ruminants. These guidelines were developed based on the results of a study of reindeer helminths in fifty zoos and menageries in the Russian Federation, conducted in 2024 under the auspices of the Union of Zoos and Aquariums of Russia. You can download the monograph at the link.

Fig. 1. External appearance of the slender eelblenny Lumpenus fabricii (top, photo by G.V. Fuchs) and the bigeye sculpin Triglops nybelini (bottom, photo by A.M. Orlov). Scientists from the P.P. Shirshov Institute of Oceanology of the Russian Academy of Sciences, the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, the Kamchatka Branch of the Pacific Institute of Geography of the Far Eastern Branch of the Russian Academy of Sciences, and the All-Russian Research Institute of Fisheries and Oceanography have obtained new data on the spatial and vertical distribution, temperature characteristics of the habitat, size-age and size-sex structure, age and growth rates, sizes and age of sexual maturity, fertility, and food composition of the slender eelblenny Lumpenus fabricii (Stichaeidae) and the bigeye sculpin Triglops nybelini (Cottidae) in the seas of the Russian Arctic (Fig. 1). Fig. 2. Distribution of Lumpen Fabricius in the Chukchi Sea. The maximum concentrations of Lumpen fabricius in the Chukchi Sea were noted in its southwestern part at depths of less than 100 m at a bottom temperature of 3.0-5.0°C (Fig. 2), and in the Kara Sea - in the very southeastern part at isobaths less than 50 m at bottom temperatures from -1.5 to -1.0°C (Fig. 3). The caught specimens were 4-9 years old, 102-268 mm long and weighing 3.1-28.3 g, however, in the Chukchi Sea the dominant specimens were 5-6 year old fish, 111-130 mm long and weighing 4-6 g, and in the Kara Sea – 6-7 year old specimens, 141-200 mm long and weighing 8-16 g. This species is characterized by sexual dimorphism in size: males are larger than females, the fertility of which varied from 115 to 436 eggs. Among specimens over 180 mm long, the proportion of females decreases sharply, reaching zero at a length over 220 mm, which is why the largest specimens of this species are exclusively males. This species is a benthophage, whose main food in the Chukchi and Kara Seas is small benthic and demersal invertebrates (mainly various polychaete worms). Fig. 3. Distribution of Lumpen Fabricius in the Kara Sea. The bigeye sculpin was recorded throughout the surveyed area of ​​the Laptev Sea at depths of 110–752 m at bottom temperatures ranging from -1.3 to +1.4ºС (Fig. 4). The catches included individuals aged 2–6 years, 66–110 mm in length, and 1.46–11.42 g in body weight, with 3–5-year-old fish 66–105 mm in length and 2–8 g in body weight dominating. Sexual dimorphism in the exterior features and sizes of mature males and females was established. Among fish over 95 mm in length, the proportion of females increases sharply, reaching 100% at over 100 mm in length. Despite the relatively wide food spectrum, the bulk of the biomass (89%) of the bigeye sculpin in the Laptev Sea is formed by hyperiids and euphausiids, which are concentrated in the bottom layer. As the size of individuals increases, the food spectrum narrows by half: the relative importance of the first of them in the diet increases sharply, while the second, on the contrary, decreases. Fig. 4. Distribution of bigeye sculpin in the Laptev Sea. Along with other small representatives of the high-latitude bottom ichthyofauna, the studied species can be considered as indicator species of the state of Arctic ecosystems. Therefore, obtaining new data on their ecology not only contributes to a better understanding of the functioning of high-latitude marine coastal ecosystems, but also allows monitoring their condition in the modern period, characterized by sharp climate changes and increased anthropogenic load (shipping, mining, fishing, tourism, etc.). The work was published in the journal Polar Biology: Tokranov, A.M., Emelin, P.O., Orlov, A.M. 2025. Distribution and biology of understudied slender eelblenny Lumpenus fabricii (Stichaeidae, Teleostei) in two Siberian Arctic seas, with comparative data on some other ground fishes // Polar Biology. V. 48. Article 17. The work was also published in the journal Fisheries Research: Tokranov, A.M., Emelin, P.O., Orlov, A.M. 2025. Distribution, life history traits, and ecological significance of bigeye sculpin Triglops nybelini (Cottidae) in Siberian Arctic marine ecosystems // Fisheries Research. V. 281. Article 107265.

Fig.1: Photos of typical representatives of the genus Lipoptena Hippoboscidae bloodsucking flies have a large number of unique morphological and physiological adaptations, most of which are closely related to their ectoparasitic lifestyle. Abdominal morphology is of great importance in the life of Hippoboscidae flies. The larva develops in the abdomen, and females lay a prepupa. Changes in abdominal morphology affect the ability of the abdomen to stretch and, therefore, to bear larvae. Representatives of the genus Lipoptena Nitzsch, 1818 have been divided into several groups according to the morphological features of the species. The genus Lipoptena itself currently includes 29 species. Modern data on the morphology and molecular phylogeny of Hippoboscidae flies show some inconsistencies in the taxonomy of this genus. Based on the morphological and molecular analysis, researchers from the A.N. Severtsov Institute of Ecology and Evolution RAS (IEE RAS) proposed a new classification of the genus Lipoptena Nitzsch, 1818. The subgenus Lipoptenella Bequaert, 1942 was elevated to the rank of genus. Fig.2: Phylogenetic tree of the family Hippoboscidae. The species L. cervi and L. fortisetosa are representatives of the genus Lipoptena Nitzsch, 1818. The species L. depressa and L. mazamae are representatives of the new genus Lipoptenella Bequaert, 1942. “In the genus Lipoptena, the morphological groups “cervi” and “capreoli” were identified, which do not coincide in composition with the groups identified earlier. A key was compiled for the genera of the subfamily Lipopteninae and keys for all species from the genera Lipoptenella and Lipoptena,” said Alexandra Yatsuk, a researcher at the IEE RAS. The work was published in the journal:A.A. Yatsuk, T.A. Triseleva, A.V. Matyukhin, E.P. Nartshuk New data on classification of Hippoboscidae (Diptera): Genus Lipoptena Nitzsch, 1818, Euroasian Entomological Journal, 23(6):353-359

Dear colleagues, dear friends! The outgoing 2024 year has become a landmark for us, full of important events and achievements. We celebrated the 300th anniversary of the Academy of Sciences, the 140th anniversary of the birth of one of the founders of our Institute, Academician Ivan Ivanovich Shmalgauzen, and the 90th anniversary of the Institute itself. This year was not easy, with its ups and downs, but we survived it and look to the future with optimism and new hopes and plans. Thanks to the well-coordinated work of our team, this 2024 year turned out to be very productive and rich in scientific, practical and educational events, including with the participation of foreign colleagues. We strengthened existing international ties, established new ones and increased the authority of our Institute in the international scientific arena. We have been actively working to improve the material and technical base, conducting expeditions and working at biological stations, publishing articles and books, organizing scientific seminars, sessions and exhibitions, and also engaged in educational activities. In the New Year, I wish that our cooperation in scientific projects becomes a source of inspiration, each project brings pride, and success becomes your constant companion! Thank you for your support and help, for your talents, experience and determination, which will become a reliable foundation for new achievements. We have achieved a lot in the past year, but we have even more plans for 2025! May the new year fulfill all your dreams and wishes, bring confidence, hope, health and well-being to every home! With best wishes, Director of the IEE RAS, Corresponding Member of the RAS S.V. Naidenko

Figure: Caucasian otter (L. l. meridionalis) in Armenia. Photo by A. Gyonjan and G. Kaloyan The nominative subspecies of the otter (Lutra lutra lutra) is widespread from Western Europe to the Russian Far East, the Caucasian subspecies (L.l. meridionalis) lives in the North Caucasus, Transcaucasia up to the north of Iran. A team of authors from Russia, Armenia and Kazakhstan compared the genetic diversity of two subspecies of river otters from Russia and Armenia using a fragment of mtDNA (820 bp) and 20 autosomal microsatellite loci. The study was attended by employees of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS): Nadezhda Sokolova, Pavel Sorokin, Jose Antonio Hernandez-Blanco. Figure 1. Median haplotype network of the mtDNA fragment (820 bp) of the river otter. EUR European Russia, CAU Caucasus (L.l. meridionalis), SIB Siberia, RFE Russian Far East, UZ Uzbekistan (L.l. seistanica). The number of mutations is indicated by dashes on the branches, the diameter of the nodes is proportional to the number of samples in the haplotype. The study described 32 haplotypes, of which 17 were new for this species. The median mtDNA haplotype network was predominantly stellate with a separate branch of haplotypes of the otter from the Russian Far East (Figure 1). The highest haplotype and nucleotide diversity was found in Far Eastern otters, and the lowest in Caucasian otters. Analysis of mitochondrial DNA and microsatellite loci also showed that Far Eastern otters are more genetically differentiated compared to otters from the European part of Russia, Siberia, and Armenia (Figure 2). Figure 2. Bayesian clustering of 117 river otter samples based on STRUCTURE analysis. Optimal value K = 2. EUR European Russia, CAU Caucasus, SIB Siberia, RFE Russian Far East. The obtained results indicate that Caucasian otters are similar to otters from the European part of Russia, while otters from the Russian Far East are genetically differentiated, have a higher genetic diversity, and probably belong to a separate genetic lineage. The study was carried out within the framework of the grant of the Russian Science Foundation №23-24-00411 The work was published in the journal: Sokolova, N. A., Oleynikov, A. Y., Korablev, N. P., Korablev, P. N., Kaloyan, G. A., Gyonjyan, A. A., Korolev, A. N., Hernandez-Blanco, J. A., & Sorokin, P. A. (2024). Genetic Structure and Diversity of Eurasian Otter (Lutra lutra) in Northern Eurasia and Caucasus: Are There Any Differences Between the Two Subspecies? Diversity, 16(12), 764.

Fig.1: Life coloration of Cheilonereis shishidoi (Izuka, 1912) from Russian waters of the northeastern Pacific Ocean. B, C – general view; D – head, dorsal view. The work presents molecular genetic analysis and data on the ecology and distribution of the symbiotic polychaete genus Cheilonereis Benham, 1916 (Polychaeta: Phyllodocida: Nereididae), which is associated with hermit crabs in the southern part of Primorye (mainly in the Peter the Great and Posyet Bays of the Sea of ​​Japan). Comparison of mtDNA COI gene marker sequences between specimens of the nereidid polychaete genus Cheilonereis from the east coast of Korea and C. cyclurus from British Columbia, Canada, revealed interspecific genetic differences of approximately 17% (p-distance – 0.173). According to our analysis, specimens collected from the Russian coast of the Sea of ​​Japan differ genetically from the C. cyclurus specimen from British Columbia by approximately 14.7% (p-distances – 0.147), while the genetic divergence with the Korean specimens is approximately 1.4% (p-distances – 0.014). Thus, the species from the northeastern Pacific Ocean should be considered a separate species, which was previously described as Cheilonereis shishidoi (Izuka, 1912). “The calculated intraspecific genetic divergence within the studied population of Cheilonereis shishidoi (n=11) living along the Russian coast of the Sea of ​​Japan is about 1.9% (p-distances – 0.019) and about 0.5% (p-distances – 0.005), respectively, in the Korean population (n=4). These results indicate that the genetic differences between the Russian and Korean populations can be considered as intraspecific,” says the author of the study, an employee of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, PhD Ivan Marin. The species described above is not the only species of nereidid polychaetes associated with hermit crabs. Thus, Cheilonereis cyclurus (Harrington, 1897) is known as a commensal of the shallow-water hermit crabs Pagurus aleuticus (Benedict, 1892), P. ochotensis, Pagurus armatus (Dana, 1851), Paguristes turgidus (Stimpson, 1857) and Elassochirus tenuimanus (Dana, 1851) (Decapoda: Paguridae) along the American coast from the Gulf of Alaska to California. Cheilonereis peristomialis Benham, 1916 is a commensal of the hermit crab Pagurus edwardsii (Dana, 1852) (= Eupagurus edwardsii) from Tasmania and South Australia (Young, 1923). Neanthes fucata (Savigny, 1822) lives in empty gastropod shells inhabited by the hermit crabs Pagurus prideaux Leach, 1815 and Pagurus bernhardus (Linnaeus, 1758) in the northeastern Atlantic Ocean, the North Sea and the Mediterranean Sea. The work was published in the journal: Marin I.N. 2024. Cheilonereis shishidoi (Izuka, 1912) is the correct taxonomic name for the nereidid polychaete species associated with hermit crabs along the Russian coast of the Sea of ​​Japan // Invert. Zool. Vol.21. No.4: 495–501.

Human activity, which actively influences global processes, has accelerated the movement of habitats of living organisms so much that it allows us to study it in real time. In Kalmykia, a new cycle of desertification has opened up the possibility of studying the movement of the habitat of a background desert rodent species, the midday gird(Meriones meridianus), which colonizes new spaces. What distinguishes the behavior of colonists who find themselves in new and unfamiliar conditions from their relatives who remain in the maternal population? Figure: Differences in boldness/curiosity scores between the maternal population (s), new colonies founded in the current year (nc), and colonies aged 1 year (c1) and 2–3 years (c2–3) for males (a) and females (b). Both males and females of the first colonists turned out to be bolder and more curious. However, after a year, male colonists become as timid as males in the maternal population. In contrast, female colonists retain the "bold" phenotype in subsequent generations, which indicates their spatial sorting during the process of range expansion: bold females end up at the forefront. The flexible reversible response of male colonists to novel conditions, on the one hand, and the stable syndrome of a bold and curious colonizer in females, on the other, represent two alternative strategies, both of which ensure colonization success, but in a sex-specific manner. We explain these differences by the fact that for usually philopatric female mammals, moving beyond the familiar ecological and social environment to empty territories represents a special challenge and requires special properties of the behavioral phenotype, including boldness. The article was published in Royal Society Open Science: Flexible males, proactive females: increased boldness/exploration damping with time in male but not female colonists Andrey V. Tchabovsky, Elena N. Surkova, Ludmila E. Savinetskaya and Ivan S. Khropov Published: 18 December 2024.

Fig. 1 Map of Chukotka and lake Elgygytgyn In the very heart of Chukotka, in the middle of the Anadyr Plateau, just north of the Arctic Circle, lies Lake Elgygytgyn (Fig. 1), formed as a result of a meteorite fall about 3.6 million years ago. Despite its inaccessibility and harsh climatic conditions, the lake has long attracted the attention of researchers. The first descriptions of Lake Elgygytgyn were made by S.V. Obruchev in 1933. Then several complex geological, geophysical and hydrological expeditions worked on the lake and its environs, the last of which, "Paleoclimate of Lake Elgygytgyn", was carried out by a joint effort of an international group of scientists in 1998-2011. As a result of the research, the scientists were able to establish that the sedimentary rocks of Lake Elgygytgyn are keepers of information about changes in the paleoclimate and paleoecology of the region over the past 3.5 million years; that the lake has never been covered by glaciers since its filling (2.9 million years ago), but has undergone significant changes in water level, as well as periods of long (over many years) stay under ice (https://paleopolar.aari.ru/ozero-elgygytgyn). All this led to the formation of a unique ecosystem, which includes both very ancient species that used the lake as a refuge, and relatively young ones that penetrated the lake during the last postglacial period and underwent adaptive radiation inside the lake. However, biological studies of the lake have so far been extremely short-term and sporadic in nature and have been devoted mainly to the study of the ichthyofauna. Fig. 2. One of the photos with a view of the lake and the scientists In 2020, employees of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) collected ichthyological and hydrobiological samples in Lake Elgygytgyn and in adjacent water bodies (Fig. 2). As a result, it was possible to reconstruct the history of the formation of the endemic ichthyofauna of Lake Elgygytgyn, describe the physiological features and diversification stages of the chars of the genus Salvelinus included in it (Esin et al., 2021; 2024). Analysis of benthic samples collected at different depths of the lake allowed us to describe several new endemic nematode species (Gusakov et al., 2022) and to discover the northernmost currently known benthic community of blind amphipods (Amphipoda), consisting of two species: Palearcticarellus hyperboreus and Pseudocrangonyx elgygytgynicus (Fig. 3). Of particular interest is the fact that the closest modern relatives of P. hyperboreus inhabit high-mountain lakes of Altai, and crayfish related to P. elgygytgynicus are found in caves in Iceland (Fig. 4). This indicates that the discovered species formed outside the lake, populated it as a result of independent waves of colonization before the onset of the Quaternary (Pleistocene) glaciation and, in the absence of competition with other amphipod species, have survived in it to this day. It is noteworthy that these crustacean species are the main food source for the deep-sea relict char species S. svetovidovi, which colonized the lake shortly after it was filled (Osinov et al., 2015; Esin et al., 2021; 2024). Fig. 3. Morphology of amphipod crustaceans (Crangonyctoidea; Amphipoda): a - Palearcticarellus hyperboreus; b/c - male and female Pseudocrangonyx elgygytgynicus Considering that earlier, in addition to endemic fish and invertebrates, endemic species of algae were discovered in the lake (Kharitonov & Genkal, 2010; Luethje & Snyder, 2021), and the benthic samples collected in 2020 included at least three new species of polychaete worms (Oligochaeta) awaiting description, Lake Elgygytgyn can be safely called a point of high endemism, requiring further more detailed study and assignment of the status of a specially protected natural area. Results published: Copilaş-Ciocianu Denis, Prokin Alexander, Esin Evgeny, Shkil Fedor, Zlenko Dmitriy, Markevich Grigorii, Sidorov Dmitry (2024) The subarctic ancient Lake El’gygytgyn harbours the world’s northernmost ‘limnostygon communityʼ and reshuffles crangonyctoid systematics (Crustacea, Amphipoda). Invertebrate Systematics 38, IS24001.

Photo: Svetlana Artemyeva Heavy metals are widespread and circulate freely on the ground, in the atmosphere and in water. In recent years, due to climate change, the total area of ​​ice cover is decreasing, glaciers are melting, and an increase in storms is contributing to the active mixing of waters. An additional contribution is made by the runoff of large rivers flowing through most of the continent. All this contributes to the influx and active transfer of heavy metals. The walrus is a good indicator of the pollution of the environment in which it lives, since it is at the top of the trophic chain and lives for about 40 years. Collecting material in different years will illustrate the dynamics of pollution. Employees of the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences (IEE RAS) managed to collect and analyze tissue samples of walruses from different regions of the Arctic. Studies of the skin of the Atlantic walrus from the waters of Franz Josef Land and the Oran Islands (Barents Sea) show a higher level of heavy metals compared to the Pacific walrus from Mechigmen Bay (Bering Sea). The level of 6 metals (cadmium, lead, copper, mercury, manganese, nickel) in the skin of the Atlantic walrus was 1.8–7.5 times higher than that of the Pacific walrus. Studies have shown that Pacific walruses have cadmium already at the early stages of embryo development. In mother-embryo and mother-calf pairs, the levels of some metals were even higher than in their mothers. And in older animals, high levels of mercury and cadmium are noted in the kidneys and liver. High concentrations of heavy metals can affect the animal's immunity, hormonal balance, reproduction and survival of cubs. Since the skin of the Atlantic walrus contains higher levels of heavy metals than that of the Pacific walrus, we assume that their level in the internal organs will also be higher. Further research is needed to clarify this issue. More details on the results in the article: Kryukova N.V., Artemyeva S.M., Samsonov D.P., Pashali A.A., Isachenko A.I., Lazareva R.E., Rozhnov V.V. 2025. Heavy metals in tissues of Atlantic (Odobenus rosmarus rosmarus) and Pacific (Odobenus rosmarus divergens) walruses // Polar Biology. Vol. 48. Is. 1 Related materials: РАН: "Морж как индикатор распространения тяжёлых металлов в Арктике" Arctic universe: "В ИПЭЭ РАН представили итоги изучения моржей в Арктике"