Features of the ecology of the sibling species M. (T.) majori and M. (T.) daghestanicus in some places of their contact on the Greater and Lesser Caucasus were studied. An analysis of symbiotopic samples of the sibling species from two localities in the Karachay-Cherkessia (the right bank of the Kizgich River and the vicinity of the village of Verkhny Arkhyz) and a mixed sample from the sympatry zone in the vicinity of the village Ankavan in Armenia was made. The obtained priority data make it possible to assert that an important condition for the coexistence of the sibling species M. (T.) majori and M. (T.) daghestanicus is their separation by residence stations, as well as by a number of environmental features. It has been shown that differences in the peculiarities of the population structure (age and sex composition), as well as in the reproduction strategy, allow the sibling species of the Caucasian pine voles to coexist in places of their contact, even under symbiotopy conditions. The previously known craniometric features, confirming differences between the sibling species of the Caucasian pine voles in food specializations, which may also be one of the factors ensuring their coexistence at the places of contact, are discussed.

   This review of world literature presents the topical taxonomy, zoogeography and toxinology of the most dangerous and poisonous snakes of the genus Naja (True cobras), including questions of origin, distribution and mechanism of toxic effect in the ecological group of “spitting cobras”. Cobras are among the most famous snakes in the world, but cobra taxonomy remained surprisingly poorly understood until the late 20th century. The application of molecular-phylogenetic research methods has led to the “Afro–Asian race for diversity”, i.e. an increase in the number of recognized African and Asian cobra species, which required the truly “revolutionary” introduction of the subgenera rank for herpetology, while maintaining the nomenclatural stability of the group of iconic species. The cobra taxonomy issues have not only an important theoretical aspect, but also purely applied (medical and zootoxinological) ones. Incomplete (or questionable) under-standing of the taxonomic position of some species may lead to dramatic errors in the treatment of snakebite poisonings, and most often – to the incorrect use of monovalent antisnake serums, since often closely and similar snake species may have poisons differing in composition, and therefore in the mechanism of action. Cobras belong to the group of primarily poisonous armed actively poisonous animals, with plastic adaptation to the environment. The current state of re-search of the unique set of polypeptide toxins in cobra venom, which serve as chemical factors (allomones) of interspecies (allelochemical) interactions, is of great theoretical and practical significance. Similar examples could be found among animals of many systematic groups, but cobras have a surprisingly balanced variety of hunting and defense methods using their poisonous apparatus – parenteral poison administration during a bite and “spitting” during remote contact.

   An analysis was carried out of the dates of the hibernation end and the beginning of spawning migrations of the fire-bellied toad and marsh frog in the valley of the middle reach of the Medveditsa river (Don basin, Saratov region) in 2023–2025. The progressive development of spring processes in the populations of these species in 2024 and their occurrence according to the false spring type in 2023 and 2025 were established. The current phenological results were compared with the retrospective time data series from 1892 to 2020 using the method of reconstructing the dynamics of the mean ten-day temperature of the environment in hibernation biotopes. The relative stability of the phenological norm of the date of the beginning of spawning migrations of the two amphibian species in the period before the onset of global warming (from 1892 to 1960) and a shift of this date to earlier dates in the period from 1961 to 2020 (by 5 days) are shown. At the end of the first quarter of the 21^st century, there was a sharp acceleration of this process (a shift of 10 days relative to the current phenological norm (mean for 1991–2020)).

   Analysis of the spatial structure of 43 populations of five species of geophytic ephemeroids of European Russia, Colchicum s. l, was carried out in 2021–2024. The distribution patterns of individuals, displayed by the Ripley function L(r)–r, were implemented in the spatstat package for the R programming language. Within the range of the genus, the occurrence frequency of populations with a random distribution type increased from north to south. In C. laetum and C. bulbocodium subsp. versicolor, which have ranges extended along geographic longitude on the Russian Plain, the populations with a contagious type of distribution of individuals were located exclusively along their northern and southern borders. Such a pattern was not observed in the species growing in the North Caucasus and mountainous Crimea. It has been shown that a random type of the spatial distribution of individuals of geophytic ephemeroids indicates homogeneity and optimality of growing conditions, and any deviations from it occur as a result of the unfavorable impact of various environmental factors. At least in Colchicum species on the Russian Plain, not so much the microrelief, microclimate or other locally manifested environmental factors, but rather the global gradients of natural and climatic conditions across the species’ range are dominant in determining the type of the distribution of individuals in populations. In those species of the genus, whose range covers mainly mountains and foothills, on the contrary, local environmental conditions probably determine the distribution type of individuals in space to a greater extent. Altitude above sea level is not a limiting factor for the distribution type of individuals in the populations of Colchicum species.

   Deratization and disinsection remain the most in-demand tools in the complex of zoonotic disease prevention to this day. Based on modern knowledge of the population ecology of the carriers and vectors of diseases, a concept has been developed and introduced into medical practice that takes into account the environmental factors of use of the methods and ways to control the numbers of reservoir animal species, ensuring the safety and effectiveness of the techniques applied. The concept includes a preliminary epizootiological survey in infectious disease foci; waiver of the practice of large-scale treatment of territories with chemicals, as well as destruction and elimination of the habitat of the target species on the premises and territories at risk of infection of the population; epidemiological focus in planning and conducting rodenticide and insecticide treatments; ensuring environmental protection measures and preserving the biological diversity of natural ecosystems.

   A study was carried out of the chrono-geographical variability of plumage color polymorphism in synanthropic populations of blue rock pigeons in five cities of the Urals and Pre-Ural regions (Chelyabinsk, Yekaterinburg, Nizhny Tagil, Serov, and Perm) from April 2020 to April 2022. In the northern population of blue rock pigeon (Serov city), the average proportion of the blue morphotype was reliably higher and the average proportion of black-chequer pigeons was lower than in more southern populations. From north to south, the proportion of black-chequer pigeons in the synanthropic populations increased and the average proportion of the blue morphotype de-creased, which was probably determined by climatic peculiarities of the locality. No significant inter-seasonal differences in the frequencies of morphotypes were revealed during the studied period. However, the interannual dynamics of frequencies of most morphotypes in separate localities had seasonal peculiarities. In the northern population (Serov city), the interannual differences in the frequencies of most morphotypes were reliable in both the spring–summer and autumn–winter periods. In the localities located to the south, reliable interannual dynamics was manifested in the spring–summer period only. Representatives of aberrant morphotypes were more sensitive to weather-climatic changes. Blue morphotype pigeons were more resistant to extreme climatic conditions. Pigeons of prevailing morphotypes (black-chequer and blue ones) reflected different behavioural strategies in the population structure formation.

   Focus on replacing synthetic fertilizers, growth regulators and plant protection products with biological products helps reducing the environmental impact, preserving biological diversity and soil fertility, and slowing down the depletion of natural resources. Plant-friendly rhizosphere microorganisms (bacteria, fungi, and algae) are of particular interest for the creation of commercial biopreparations (biofertilizers, biostimulants, and biological control agents). The article provides a review of research publications devoted to the production and use of agricultural biopreparations (inoculants) based on plant growth-promoting microorganisms (PGPR), plant growth-promoting fungi (PGPF) and eukaryotic microalgae. According to available estimates, the biofertilizer market volume should reach $ 2.83 billion in 2025. Large companies operating in the biopreparation market focus on the development of innovative products that can increase the suppressive capacity and fertility of soils by improving microbial diversity, increasing the availability of nutrients, and suppressing dangerous phytopathogens. The leading trend of recent decades has been the orientation of producers toward the introduction of genetic engineering technologies that allow inoculants to be adapted to the specific needs of agricultural crops, to increase their efficiency and resistance to adverse factors, and to ensure successful integration with indigenous microbial communities. The main tasks in the field of biotechnology in modern science include confirmation of the quality of bioproducts, increase in their shelf life, guarantee of their efficiency, cost price reduction, and provision of environmental and sanitary safety. To ensure the proper quality of biopreparations and the guaranteed effect of their use, it is necessary to develop technologies for the production of large quantities of pure (free from other microorganisms) inoculants with a high infection potential.

   Biological invasions are a serious global challenge of our time, with invasive species causing significant losses of biodiversity and ecological services. The aquarium and ornamental pet trade is one of the major sources of alien species worldwide. One of the most popular aquarium fish is the goldfish Carassius auratus (Linnaeus, 1758), an ornamental fish native to East Asia that has be-come cosmopolitan due to aquarium hobbyists. This notorious invasive fish was known from only few localities in natural ecosystems of North Africa. In this paper, we provide new information on the current distribution and presence of this invasive species in Morocco, as well as we discuss the role of aquarium trade in its introduction into new freshwater ecosystems of the country.