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Pseudochaenichthys georgianus In the South Georgia icefish, 16 helminth species were recorded (from 3 to 12 species per host), including 3 species of trematodes, 4 species of cestodes, 5 species of nematodes and 4 species of acanthocephalans (table 3). Estimated species richness was 18 (Chao1), 19 (jackknife) or 17 (bootstrap) species. The diversity indices equalled 1.54 (Shannon), 0.68 (Simpson), and 0.55 (Pielou’s evenness). All the cestode species, as well as the nematodes Anisakis sp., Contracaecum sp. and Pseudoterranova sp. and acanthocephalans Corynosoma spp. parasitize P. georgianus on larval stages. Thus, P. georgianus is considered to be a definitive host for 6 out of 16 helminth species recorded. As in the mackerel icefish, cestodes predominated in the helminth community of P. georgianus; together they comprised 78.7 % of the total helminth number (fig. 1). According to the prevalence of infection, 8 species predominated in the helminth community in P. georgianus (table 3). Bilocular and trilocular metacestodes had an infection prevalence higher than 95 %. The cestode Diphyllobothrium sp., the trematodes M. pennelli and N. georgiensis, the nematodes Contracaecum sp. and Pseudoterranova sp. had an infection prevalence of 70–95 %. The nematode D. fraseri and monolocular metacestodes were common, with the infection prevalence of 36.4 % and 45.5 %, correspondingly. Other 8 species of helminth occurred in less than 30 % of examined P. georgianus. In all three latter fish species, the proportion of helminth species found on larval stages was larger (62.5–75 %) than that of the species represented by adult parasites (25–37.5 %) (fig. 2). The helminth species richness appeared to be much higher in fishes from shallowwater (10–30 m deep) habitats than in deep-water (60–800 m) habitats (table 4). Analysis of similarity between helminth faunas in studied samples of shallow- and deepwater fishes (table 5) revealed the highest similarity of helminth faunas in two shallow-water species from the Ukrainian Antarctic Station area: P. charcoti and N. coriiceps (SØrensen index 90.6 %) and C. aceratus with N. coriiceps and P. charcoti (88.0 % and 89.8 %, respectively). Also, helminth faunas of deep-water populations of C. aceratus and P. georgianus were similar (SØrensen index 88.9 %). The lowest similarity was recorded for the helminth fauna of the deep-water population of C. gunnari; the similarity between N. coriiceps and C. gunnari was minimal (20.0 %). Visualization of the helminth faunal similarities according to the Bray-Curtis index using the cluster analysis (fig. 3) showed a clear division of groups of shallow- and deepwater fish species. According to the results of the SIMPER analysis, the overall dissimilarity between the helminth communities of shallow- and deep-water fishes was 80.1 %. Four helminth species had the largest contribution to the dissimilarity: the acanthocephalan Corynosoma pseudohamanni (19.4 % contribution), anisakid nematodes Contracaecum sp. (17.4 % contribution) and Pseudoterranova sp. (14.4 % contribution), and trilocular metacestodes (11.4 % contribution). Infection of shallow-water fishes with C. pseudohamanni and anisakid nematodes was more than 10–15 times higher, while deep-water fishes had 168 times higher infection with trilocular metacestodes., Published as part of Kuzmina, T. A., Salganskiy, O. O., Vishnyakova, K. O., Ivanchikova, J., Lisitsyna, O. I., Korol, E. M. & Kuzmin, Yu. I., 2022, Helminth Diversity In Teleost Fishes From The South Orkney Islands Region, West Antarctica, pp. 135-152 in Zoodiversity 56 (2) on page 142, DOI: 10.15407/zoo2022.02.135, http://zenodo.org/record/7175665

Kuzmina, T. A., Salganskiy, O. O., Vishnyakova, K. O., Ivanchikova, J., Lisitsyna, O. I., Korol, E. M., Kuzmin, Yu. I. (2022): Helminth Diversity In Teleost Fishes From The South Orkney Islands Region, West Antarctica. Zoodiversity 56 (2): 135-152, DOI: 10.15407/zoo2022.02.135, URL: http://dx.doi.org/10.15407/zoo2022.02.135

Chaenocephalus aceratus In the blackfin icefish, 19 helminth species were recorded (from 3 to 13 species per host), including 3 species of trematodes, 4 species of cestodes, 5 species of nematodes and 7 species of acanthocephalans (table 3). Estimated species richness was 20 (Chao1), 24 (jackknife), or 22 (bootstrap) species. The diversity indices equalled 1.88 (Shannon), 0.78 (Simpson), and 0.63 (Pielou’s evenness). All the cestode species, as well as nematodes of the genera Anisakis, Contracaecum and Pseudoterranova and acanthocephalans of the genus Corynosoma parasitized this fish host on the immature stages. Thus, C. aceratus is considered to be a definitive host for 7 out of 19 helminth species recorded. Nematodes predominated in the helminth community of blackfin icefish, they comprised 44.99 % of the total helminth number. The proportion of other groups of helminths was lower: 30.96 % for cestodes, 13.61 % for acanthocephalans, and 10.43 % for trematodes (fig. 1). According to the prevalence, three species predominated in the helminth community in C. aceratus: the cestode Diphyllobothrium sp. (P = 100 %), the trematode N. georgiensis (P = 95.5 %), and the nematode Pseudoterranova sp. (P = 95.5 %) (table 3). Five other helminth species had an infection prevalence higher than 50 % and may be considered as subdominant species: bilocular and trilocular metacestodes, the nematode Contracaecum sp., and the acanthocephalans C. bullosum and C. hamanni. The nematode D. fraseri and the acanthocephalan C. evae were common, with an infection prevalence of 45.5 %. Other 10 species of helminths were found in less than 30 % of examined C. aceratus., Published as part of Kuzmina, T. A., Salganskiy, O. O., Vishnyakova, K. O., Ivanchikova, J., Lisitsyna, O. I., Korol, E. M. & Kuzmin, Yu. I., 2022, Helminth Diversity In Teleost Fishes From The South Orkney Islands Region, West Antarctica, pp. 135-152 in Zoodiversity 56 (2) on page 141, DOI: 10.15407/zoo2022.02.135, http://zenodo.org/record/7175665

The charge transport on the electrically charged surface of polytetrafluoroethylene (PTFE) films in the presence of the adsorption of an electrically conductive phase has been studied. The attenuation of the rate of displacement of the potential drop over the film surface, which limits the area of its expansion, has been found. An estimate has been made for the critical index of the correlation length of a percolation cluster that forms on an electrified PTFE surface at high humidity. It has been experimentally established that the leak of charge from an electrically charged surface is determined by percolation processes. Keywords: percolation, percolation threshold, adsorption, electrization.

Prosthogonimus ovatus (Rudolphi, 1803) One adult specimen was collected from the bursa of Fabricius of one bird. L o c a l i t y: Horodnia District (Chernihiv Region). Description. Body pear-shaped (fig. 1, B), 1,899 long; its maximum width 735 in posterior quarter. Oral and ventral suckers subspherical. Oral sucker 130×136. Ventral sucker 250×263. Distance from anterior end of body to centre of ventral sucker 870. Pharynx well developed, round, 106×88. Testes elongate-oval. Right testis 283×220. Left testis 260×180. Cirrus-sac 350×80. Ovary 165×313. Ventral sucker totally covering ovary. Anterior border of uteri loops distal to intestine bifurcation, posterior border of uteri loops almost at end of body. Anterior edge of vitellarium at level of anterior border of uteri loops. Branches of vitellarium different in size. One branch extending to middle of testes. Another branch extending to end of testes. Eggs oval, numerous, 25–28× 13–14 in size., Published as part of Syrota, Ya. Yu., Korol, E. M. & Kuzmin, Yu. I., 2020, New Records Of Helminths Of The Corncrake, Crex Crex (Aves, Rallidae) From Ukraine, pp. 11-16 in Zoodiversity 54 (1) on page 13, DOI: 10.15407/zoo2020.01.011, http://zenodo.org/record/6377534

Brachylaima fuscata (Rudolphi, 1819) Six specimens were collected from the intestine of one bird. L o c a l i t y: Nizhyn District (Chernihiv Region). Description (based on 4 mature specimens). Body elongated (fig. 1, A), with maximum width 476–542 anterior to ventral sucker; body length 2,487 –2,849. Oral sucker larger than ventral sucker. Oral sucker 241–288×211–282. Ventral sucker 150–182×145–180. Distance from anterior end of body to centre of ventral sucker 890–960. Pharynx well-developed, round, 102–174×123–168. Gonads in posterior quarter of body. Ovary between testes. Anterior testis 160–272×167–261, posterior testis 164–269×122–245. Ovary 131–162×136– 171. Vitellarium distributed in two lateral fields, extending from posterior extremity of ventral sucker to level of anterior edge of anterior testis. Eggs oval, numerous, 28–35× 16– 18 in size., Published as part of Syrota, Ya. Yu., Korol, E. M. & Kuzmin, Yu. I., 2020, New Records Of Helminths Of The Corncrake, Crex Crex (Aves, Rallidae) From Ukraine, pp. 11-16 in Zoodiversity 54 (1) on page 12, DOI: 10.15407/zoo2020.01.011, http://zenodo.org/record/6377534

Prosthogonimus cuneatus (Rudolphi, 1809) Two specimens, one adult and one immature, were collected from the bursa of Fabricius of one bird. L o c a l i t y: Horodnia District (Chernihiv Region). Description of an adult specimen. Body oval (fig. 1, C), 2,072 long, with maximum width 752 atlevel of ovary. Oral sucker subspherical, 191×212. Ventral sucker 351×360. Distance from anterior end of body to centre of ventral sucker 930. Pharynx well developed, oval 105×96. Oesophagus short, 120–190 long. Testes elongate-oval. Size of right testis 200×96, size of left testis 198×90. Cirrus sac 220×44. Ovary 220×300. Ventral sucker slightly overlapping ovary anteriorly. Loops of uteri extending from posterior edge of ventral sucker to posterior end of body. Vitellarium at lateral margins of body. Anterior border of vitellarium at level of posterior edge of ventral sucker, posterior border of vitellarium posterior to posterior edge of testes. Eggs oval, numerous, 23–25× 14–15 in size. Description of an immature specimen. Body pear-shaped, 1,425 long, with maximum width 580 at level of testes. Size of oral sucker 168×160, size of ventral sucker 265×260. Pharynx 55×35. Distance from anterior end of body to centre of ventral sucker 660. Testes round. Right testis 148×150, left testis 150×153. Ventral sucker partly covering anterior part of ovary. Ovary 147×178. Vitellarium undeveloped., Published as part of Syrota, Ya. Yu., Korol, E. M. & Kuzmin, Yu. I., 2020, New Records Of Helminths Of The Corncrake, Crex Crex (Aves, Rallidae) From Ukraine, pp. 11-16 in Zoodiversity 54 (1) on pages 12-13, DOI: 10.15407/zoo2020.01.011, http://zenodo.org/record/6377534

Cardiofilaria pavlovskyi Ström, 1937 Two specimens (males) were collected from the air sacs of two birds. L o c a l i t y: Kyiv Region, near Kyiv. Description of 2 males. Nematodes of small size. Body cylindrical, slightly narrowing to anterior and posterior extremities (fig. 2, A), 6,431 –7,485 long. Body width 110–115 at level of posterior edge of oesophagus. Maximum body width 143–165 near middle of body. Cuticle smooth. Mouth small, dorso-ventrally elongated in studied specimens. On anterior extremity, 4 pairs of papillae in two circles and lateral amphids (fig. 2, B, D). Distinct cuticular ring surrounding buccal cavity. Oesophagus divided into muscular and glandular parts, border between parts indistinct. Muscular part of oesophagus 48–51 long, glandular part 355–377 long. Nerve ring in first quarter of glandular part of oesophagus, 127–136 from anterior extremity. Spicules subequal and slightly dissimilar (fig. 2, C). Left spicule 75–81 long, right spicule 60–65 long. Tail short and blunt, 69–76 long., Published as part of Syrota, Ya. Yu., Korol, E. M. & Kuzmin, Yu. I., 2020, New Records Of Helminths Of The Corncrake, Crex Crex (Aves, Rallidae) From Ukraine, pp. 11-16 in Zoodiversity 54 (1) on page 14, DOI: 10.15407/zoo2020.01.011, http://zenodo.org/record/6377534, {"references":["Strom, Z. K. 1937. A new nematode of birds Cardiofilaria pavlovskyi n. gen., n. sp. In: Trudy Sov. Izuch. Proizvod. Sil. Ser. Turkm, 9. 217 - 221 [In Russian]."]}