The common frog (Rana temporaria) and the moor frog (R. arvalis) lived in all green areas of Moscow until the end of the 20th century. The reduction in the area of woody vegetation, the destruction of breeding sites and introduction of the invasive fish Perccottus glenii contributed to the extinction of these amphibians in most of the city. The paper provides information on the distribution of brown frogs in Moscow based on the results of monitoring in 2020. R. temporaria was found in 37 localities in the Northwestern (6 points), Northern (3 points), Northeastern (1 point), Eastern (9 points), Southeastern (1 point), Southern (5 points), Southwestern (5 points) and Western (7 points) administrative districts. Eleven finds (29.7%) are located outside of specially protected natural areas. Most of the species’ habitats (30 points, or 81.1%) are isolated from other populations. R. arvalis was found in 14 localities in the Northwestern (3 points), Northern (3 points), Eastern (4 points), Southwestern (1 point) and Western (3 points) administrative districts of Moscow. Of all the finds noted, three ones (21.4%) are located outside of specially protected natural areas. The vast majority of the habitats of the species (10 points, or 71.4%) are isolated.

The state of the grass snake (Natrix natrix) population in the Mordovian State Nature Reserve was assessed using the hematological approach. The leukocyte blood count was estimated together with calculation of the associated leukocyte indices (neutrophil:lymphocyte (N:L), eosinophil:lymphocyte (E:L), heterophil:eosinophil (H/E) and heterophil:lymphocyte (H:L) ratios). The surface area of leukocytes (heterophils, basophils, eosinophils, azurophils, monocytes, and lymphocytes) was measured. The leukocyte blood composition of Natrix natrix was characterized by the predominance of agranulocytes, and the granulocyte fraction was 31– 37% (u = 1.99, p = 0.04). The population pattern of the leukocyte blood composition of Natrix natrix was as follows: heterophils – 8.07±0.6%, basophils – 12.33±0.95%, eosinophils – 8.33±0.65%, azurophils – 5.25±0.53%, monocytes – 9.77±0.42%, and lymphocytes – 56.22±1.7%. According to the averaged area, the leukocytes were arranged in the following order: eosinophils – monocytes – azurophils, basophils – heterophils – lymphocytes. The diameter of the largest cells (eosinophils) was (17.5±2.42) μm. The smallest lymphocytes had diameters within (7.22±1.21) μm. The absence of any differences in the quantitative content of all types of granulocytes and agranulocytes in the blood of the grass snake from different parts of the reserve indicated a comparable level of impact and the identity of the physiological mechanisms of adaptation that occur in the body of animals in protected habitat conditions. Most of the leukocyte integral indices revealed the same type of variability in the parameters of the white blood cell system of the Natrix natrix in three areas of the reserve, with the exception of an increased value of the heterophiles/lymphocytes ratio in the sample from the village Pushta. The increase in this indicator made it possible to draw a conclusion about the stress effect on the individuals of this sample. The principal component method was used to differentiate the samples of the grass snake with a more complete quantitative description of the leukocyte composition of the objects of study; the results obtained are presented in a visual, integrated and generalized form. The use of the principal component method made it possible to combine samples of Natrix natrix with similar indicators of leukocyte composition, as well as to identify a population of Natrix natrix that differs in its indicators in the urbanized territory of the Samara region. The blood pattern and the dynamics of blood leukocyte indices reflected the active response of the Natrix natrix body to the complex of environmental factors of the habitat on the territory of the Mordovian State Nature Reserve.

The publication describes the history of the formation of the Department/Laboratory of Herpetology in the Zoological Institute of Russian Academy of Sciences and previously unknown facts of the biography of its staff. An overview of the events dedicated to the celebration of the centenary anniversary of the establishment of the Department is given.

Detailed morphological characteristics of the populations of Coronella austriaca on the northern border of its range, in the Vladimir and Nizhny Novgorod regions, are presented. L.corp. of males and females reaches 543 mm and 601 mm, respectively. Ventr. is 166–175 and 175–189, respectively, Scd. Is 50–59 and 32–56, Lab. left/right is usually 7/7 (89.7%), Sublab. is 9/9 (72.4%), respectively. A high incidence of asymmetry (44.4%) was noted for Temp. I and II rows; of 23 combinations, the most common is the symmetric one 2+3/2+3 (25.9%). L.corp./L.cd. limits overlap in 3.1% of underyearlings and yearlings, and in 1.8% of adults. Same-sex individuals statistically significantly differ in their meristic characteristics within the studied regions: the females from a locality near the Chucha river differ from the rest ones in Scd. and Sublab.left., males differ in Scd. and Ventr.+Scd.; males also significantly differ in their metric characteristics L.corp., L.cd., L.total.

A comparative estimation of the leukocyte profile of the marsh turtle Emys orbicularis (Linnaeus, 1758) living in the Ural river basin (Orenburg region, Belyaevsky district, 11 females and 5 males) and in the Volga river basin (Astrakhan region, Krasnoyarsk district, 28 females and 20 males) was made. The blood formula (WBC) of males and females was calculated together with the calculation of integral leukocytal indices (the lymphocyte-granulocyte index, the leukocyte shift index, the heterophile/lymphocyte ratio, the heterophil/eosinophil ratio, and the lymphocyte/eosinophil ratio). Lymphocytes were the predominant leukocyte cells in the peripheral blood of Emys orbicularis (40–45%). Among granulocytes, heterophiles (the population from the Orenburg region) or basophils (the population from the Astrakhan region) predominated. The absence of any differences in the quantitative indicators of the blood formula and integral indices for males and females indicated a comparable level of impact and identity of the physiological adaptation mechanisms occurring in the animals in the Orenburg region. Intersexual differences were manifested in an increased content of monocytes (u = 3.13, p = 0.001), which indicated activation of the natural immunity of males in comparison with females from the Astrakhan region. The leukocyte composition of the Emys orbicularis blood differed in the content of granulocytes and agranulocytes in different populations. The males from the Orenburg region differed from those from the Astrakhan region by an increased proportion of heterophiles and a reduced content of basophils. Females differed in all blood count parameters, except for eosinophils whose fraction was equal (u = 0.71, p = 1.00). In the peripheral blood of females from the Orenburg region, a higher content of heterophiles, monocytes and a lower content of basophils and lymphocytes were found in comparison with those from the Astrakhan region. Quantitative-qualitative changes were detected in the leukocyte composition of the blood during the invasion of hemoparasites. The specific immune response (the content of lymphocytes) decreased, and the nonspecific defense system (the content of heterophiles) increased. The maintenance of the immunological reactivity of the organism under the conditions of invasion was determined by the functional activity of heterophiles, which was confirmed by a higher value of the heterophil/lymphocyte index. The blood formula (WBC) and the dynamics of leukocytal indexes of Emys orbicularis reflected the active response of the organism to a complex of environmental factors, including parasitic invasions.

Arecord of Rana temporaria on the ice cover of the Gulf of Finland is described. Frog slowly moved on the ice surface with speed around 0.03 m/s. Air temperature near ice surface was +3.5°C, and the frog body temperature was +4°C. In the Saint Petersburg region, common frogs can hibernate in the coastal waters of Baltic Sea with salinity of 0 – 5.8‰.

The paper presents the results of our long-term (August 2014–October 2016) observations of changes in some properties of the poisonous secretion of eastern steppe vipers of the nominative subspecies Vipera renardi renardi (Christoph, 1861) during their postembryonic ontogenesis. The poisonous secretion of newborn vipers differed from the venom of adult snakes by an increased protease activity and the absence of any L-amino acid oxidase activity; all newborns had colorless venom. Adults produce venom either colorless, where no L-amino acid oxidase activity is detected, or yellow, where it is detected. It was found that the enzymatic activity of the venom of young vipers between their first and second winterings corresponded to the level of adults. After the second wintering, young vipers showed statistically insignificant seasonal changes in the activity of proteases and L-amino acid oxidase.

The paper discusses the distribution of Nikolsky’s pitviper, Gloydius caucasicus, in Azerbaijan. According to the authors’ own research results, literature data and museum collections, 32 findings of this species in the Jalilabad (1 locality), Yardymly (11 localities), Lerik (10 localities), Lenkoran (10 localities) and Astara (5 localities) administrative districts are presented. All the known findings of the pitviper are located within 10–1,980 m above sea level in the Lenkoran lowland, the mountain forest belt of the Talysh Mountains, as well as in the mountain-xerophytic steppe of the Yardymly, Deman and Diabar intermountain depressions. The species is recorded on the territory of “Hirkan” National Park and Zuvand regional reserve. G. caucasicus is a rare snake species in Azerbaijan. The main threat to the pitviper in the region is habitat loss. To preserve the species in the northwestern periphery of the habitat, the authors recommend creating a specially protected natural area in the Jalilabad and Yardymly districts on the Alashar-Burovar Ridge. It is also necessary to include G. caucasicus into the Red Data Book of the Republic of Azerbaijan in the category “Vulnerable species” (VU).

The paper provides new information on the distribution of rare and endangered snakes over the Stavropol Region, namely, Eryx jaculus, Dolichophis caspius, Elaphe sauromates, and Platyceps najadum.

For the first time, the amplitude-frequency and temporal characteristics of the acoustic signals (the distress one and two types of advertisement calls) of the Crimean gecko (Mediodactylus danilewskii) were analyzed. The distress call is a rather long one (usually around 150–350 ms, but sometimes up to nearly 1 s), with a peak frequency of 6.86 kHz in both males and females. The upper harmonics of this type of signal lie in the ultrasonic region of the frequency spectrum. The short advertisement call has a different duration in males and females, namely, about 23 ms and 35–40 ms on average, respectively. The peak frequency of this type of signal is 4.82 kHz in both sexes. Some frequency parameters of the acoustic signals are characterized by lower values in males than those in females, despite the larger body sizes of the latter. E.g., 35% and 11% of the total distress call energy is below 4 kHz in males and females, respectively. The average value of the fundamental frequency of short advertisement calls in males and females is 1.75 kHz and 3.33 kHz, respectively, while the limits of variability of this parameter in representatives of both sexes almost do not overlap. The prospects of using bioacoustics for solving important issues of the Mediodactylus (kotschyi) superspecies taxonomy are discussed. We assume that the male long advertisement call, which is a sequence with a duration of 4 to 9 s consisting of 24–44 clicks with an average peak frequency below 4 kHz following each other at a rate of 6.4–9.1 clicks/s, will be most informative for these goals.