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Phenotypic and genetic estimations of entomopathogenic ascomycete Beauveria bassiana (strain Sar-31) after 6-passaging through four hosts were shown. Increasing of virulence, changes in morpho-cultural characteristics and variations in Inter Simple Sequence Repeats (ISSR) assay between initial and reisolated cultures were registered. Six passages of entomopathogenic ascomycete Beauveria bassiana (strain Sar-31) through four hosts (Galleria mellonella, Tenebrio molitor, Leptinotarsa decemlineata, Locusta migratoria) and following estimation of phenotypic and genetic differences of the initial strain and reisolated cultures were conducted. The passaging of strain through certain host led to increasing of virulence for both this host and other test-insects. Unidirectional changes of morpho-cultural characteristics: colonies pigmentation and relief strengthening, increasing of conidia production and lipolytic activity were registered in all passaged cultures. Genetic analysis with 6 ISSR markers revealed variations between initial and reisolated cultures in 3 markers. Taken together, the results of this study help us understand potential ways of fungi strains changes during epizootic process and possibilities of ISSR assay applying for investigation of pathogen transmission.

Morphological features of Rauschitaenia ancora (Mamaev, 1959), a cestode with atypical mode of attachment ("anchoring" in the wall of the host intestine), are considered. At the center of the overgrown scolex there is a rostellum, size of which is close to that of the developed metacestode. Large suckers are composed mainly of loose parenchyma and fine radial muscle fibers. Fragments of host tissue are noted in the suckers' cavity. Surface of the scolex is covered with large microtriches, which are in contact with the host tissue having signs of degradation. Distal cytoplasm is filled with vesicles coming from tegumental cytons. Rostellar glands that are common to cyclophyllids are not found. Excretory canals contain fluid (closer to the surface) and numerous lipid droplets (deeper located canals).

The number of larvae in the Cosmocerca ornata (Dujardin, 1845) females from marsh frogs in vivo and period of larvae production of nematodes in vitro was studied. The number of larvae in females of nematodes and quantity of born larvae depend on the size of parasites. The largest C. ornata females had the highest number of larvae and the longest period of larvae production. The nematode sizes in its turn depends on density of infrapopulation of C. ornata and ambient temperature. The dependence of a number of the C. ornata larvae on the host age and sex and on a season of the year was revealed. Different phenotypes of amphibians showed no influence on the number of larvae inside nematode females. In the experiment C. ornata females remained viable up to 8 days, producing larvae up to 7 days. The optimum temperature for the larvae production constituted 24—28°C. At a temperature of 12°C and lower the nematode larvae output from females was stopped.

The taiga tick (Ixodes persulcatus, Schulze, 1930) is the main and most epidemiologically dangerous vector of tick-born encephalitis virus (TBEV) and Borrelia in most parts of Russia's territory (Alekseev et al., 2008). The purpose of this article is to describe the incidence rate of I. persulcatus males with exoskeleton anomalies in populations of the Asiatic part of Russia. A total of 2630 taiga tick males were morphologically analyzed. They were collected in Far Eastern, Siberian and Ural Federal Districts (respectively, FEFD, SFD, UFD) in 15 geographically remote locations. It is shown that in all populations there are adult ticks with impaired exoskeleton, among which two types dominate: twin dents at the back of conscutum (P11), and uneven surface of conscutum — a "shagreen skin" (P9). The frequency of abnormalities in males from the areas with temperate monsoon and temperate continental climate (FEFD) was definitely lower (6.5 ± 1.05%), than in individuals from the territories of SFD (29.7 ± 1.03 %) and UFD (25.8 ± 3.93 %) with continental and sharply continental climate. FEFD territory is also characterized by a less number of males having two simultaneous exoskeleton anomalies. Similar district-preconditioned differences in the frequency of recorded body distortions are also typical of females, with a higher percentage of deviant individuals in comparison with males. Thus, the identified polymorphism of exoskeleton structure of the taiga tick may reflect the natural phenogeographical variability of this trait and might not be the result of human impact.

A case of tundra vole death as a result its hyperinvasion by ticks Ixodes angustus on the northern periphery of the Asiatic range of the parasite is given.

The Pacific saury Cololabis saira (Brevoort, 1856) is one of the important target species of commercial fisheries. Food manufacturers and consumers encounter problems due to the infection of the saury by acanthocephalans, which are quite difficult to clean out completely during on-board catch processing. Infection of C. saira was not studied on a regular basis, therefore, our knowledge about the parasites of saury is fragmentary. This paper contains infection indices (only acanthocephalans) of the Pacific saury caught in the Kuril Islands area (Russian Exclusive Economic Zone) in 2015.

The simplest modification of the dynamic extraction method using cottonwool filter based on the Baermann funnel principle, is described. This modification excludes the funnel because a great share of sticky worms attach to sloping walls of a funnel and thus do not reach the collector Eppendorf tube. But the main principle of the Baermann funnel is used, i. e. sinking down of actively moving heavy narrow bodies via wide holes of filter and thus separating the active worms from passive non-Brownian moving substrate particles, which do not pass the filter and remain above it. This principle is illustrated because it has never been described before. In the proposed modification any sloping walls in the extraction paths are excluded and thus the probability to attach sticky nematodes to walls is also excluded; only cylindrical equipment with abrupt vertical walls is used; procedures are extremely simplified to be user-friendly for beginners: only filter (cotton pads), Eppendorf tubes, plastic glasses and narrow PVC tubing are applied. The new simplified modification allows one to collect nematodes by non-professional workers, e. g. in Polar expeditions without microscopic study of results. As an addition, an efficient method to maintain extracted nematodes alive is proposed, using the "effect of water film" in foam rubber inside the Eppendorf tube. To maintain nematodes alive during several months it is recommended to suppress bacteria via addition of 0.2—0.4% formaldehyde solution and then keep the tube with nematodes in a refrigerator.

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The publication dedicates to the life story of well-known Soviet parasitologist-helminthologist, Prof. Maria Mikhailovna Belopolskaya on the occasion of her 100th anniversary. Complete autobiography and some record of conversations between the hero and the author were used for the article. The publication is illustrated with several photos of the scientist made in different years.

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