Keywords
terrestrial snail; Stenomphalia; Caucasus region;
Pages
pp. 1 -
6

Additional material collected in September 2019 made it possible to clarify the range of conchological variability of Harmozica zangezurica recently described from the Syunik region of Armenia, which largely overlaps with that of Harmozica pisiformis thus rendering impossible the reliable identification of empty shells. At the same time the stability has been proven of a diagnostic feature of H. zangezurica – very long vaginal appendages whose length is approximately equal to the total length of the penis and epiphallus,. This character allows reliable distinguishing of H. zangezurica not only from the conchologically similar species H. pisiformis, but also from other representatives of the genus Harmozica. Some data on the ecology and life cycle of H. zangezurica were obtained.

Harmozica zangezurica (Gastropoda, Pulmonata, Hygromiidae) – криптический вид наземных моллюсков с юга Армении
Гураль-Сверлова Н. В.; Гураль Р. И;
Keywords
Unionidae; glochidia; SEM preparation;
Pages
pp. 7 -
20

Mature glochidia of freshwater bivalves can give additional features for taxonomic revisions. To study morphology of glochidia with the scanning electron microscope (SEM), special collecting techniques, storage and preparation are required. Based on extensive personal experience, an overview of various techniques is presented, both positive and negative. The interactions of chemicals used for the storage of glochidia and dissolution of glochidial tissue are described. Techniques for cleaning and mounting the glochidial shells of Unionidae for investigations by SEM are described and compared.

Методика подготовки раковин глохидиев (Bivalvia, Unionidae) для работы на сканирующем электронном микроскопе
Саенко Е.М.; Казарин В.М.;
Keywords
alien molluscs; population structure; Central Russian Upland; Hygromiidae; Enidae;
Pages
pp. 21 -
39

Studying of the demographic characteristics of populations of alien species at the stage of expansion makes it possible to assess their invasive potential. Field studies of alien terrestrial gastropods Xeropicta derbentina (Gastropoda, Stylommatophora, Hygromiidae), Brephulopsis cylindrica (Gastropoda, Stylommatophora, Enidae) and Harmozica ravergiensis (Gastropoda, Stylommatophora, Hygromiidae) have been carried out in Belgorod city, the southern part of the Central Russian Upland (Russia). All studied species are native to the Black Sea region and the Caucasus; in the southern part of the Central Russian Upland, they have been registered over the past ten years. The population density, demographic structure, and spatial structure have been analyzed for three years of observations (2017, 2019, 2020). During this period, the changes in the population density have been noted for all studied species. The most pronounced changes have been observed in X. derbentina, whose population density has significantly decreased, and the spatial structure has changed from clustered type to random distribution. In addition, the age structure of X. derbentina population had a pronounced change at the beginning of the snail activity season of 2020.

The expansion of the other two invaders, B. cylindrica and H. ravergiensis, is proved as more successful. At the same time, H. ravergiensis is distributed throughout the city. This species has stable population density and random type of spatial population structure on most sites. B. cylindrica has the highest population density: in 2020, it has reached 406 ind./m2 on average, with the maximum of 1215 ind./m2. Meantime, the species keeps the clustered spatial structure, which is explained by both high population density and adaptation to the arid conditions of its natural range.

Демографическая и пространственная структура популяций некоторых чужеродных видов наземных моллюсков на территории Белгорода (Среднерусская возвышенность)
Адамова В.В.; Украинский П.А.; Крымская О.В.;
Keywords
North-West Pacific; Coryphellidae; integrative systematics; biodiversity; pseudocryptic species; species delimitation;
Pages
pp. 41 -
48

A new species of the family Coryphellidae, Coryphella alexanderi sp. nov. is described based on specimens collected in the Kuril Islands, North-West Pacific, from the upper sublittoral to 200 m depth. An integrative analysis was conducted, including a molecular phylogenetic analysis based on four markers (COI, 16S, H3, 28S), an automatic species delimitation method ABGD, and an analysis of the external and internal morphology using light and scanning electron microcopy. The distinctiveness of Coryphella alexanderi sp. nov. is well established both morphologically and genetically, and it differs from externally similar species in radular characters. Phylogenetically Coryphella alexanderi sp. nov. is closely related to Coryphella trophina, which occurs sympatrically in the same geographic and bathymetric ranges. Coryphella alexanderi sp. nov. appears to be restricted to the middle and northern Kuril Islands, which is consistent with the high numbers of endemic taxa in this area.

Новый вид рода Coryphella (Gastropoda: Nudibranchia) из прибрежных вод Курильских островов
Екимова И.А.;
Keywords
Istria; Ruthenica filograna pocaterrae; new subspecies;
Pages
pp. 49 -
52

On the territory of Republic of Croatia a new subspecies of land snails of the clausiliid genus Ruthenica has been found. Illustrated description is presented. New subspecies differs from other in shell shape, semi-apostrophic aperture and sculpture pattern.

Новый подвид Ruthenica filograna (Pulmonata: Clausiliidae) из Хорватии
Егоров Р.В.;
Keywords
schoolmaster gonate squid; species; subspecies; taxonomy; Bivalvia) from the Sea of Japan;
Pages
pp. 53 -
59

Two subspecies of the schoolmaster gonate squid Berryteuthis magister (Berry, 1913) have been described to date: B. magister nipponensis Okutani et Kubodera, 1987 from the Pacific Ocean off the coast of Japan and Sea of Japan, and B. magister shevtsovi Katugin, 2000 from the Sea of Japan. The gonatid species Gonatus septemdentatus Sasaki, 1915, which was later recognized as a junior synonym of B. magister, was also described from the Sea of Japan. Comparisons among these three taxa and with the nominative subspecies using morphological and ecological features suggest that individuals of the genus Berryteuthis inhabiting the Sea of Japan belong to the species B. septemdentatus (Sasaki, 1915), which should be considered the valid name for this taxon.

Таксономическое положение кальмаров рода Berryteuthis Naef, 1921 (Gonatidae, Oegopsida) из Японского моря
Алексеев Д.О.; Катугин О.Н.; Бизиков В.А.;
Keywords
replacement name;
Pages
pp. 60 -
60

The new replacement name Takashius nom. nov. is proposed to solve the homonymy between the fasciolariid genus Okutanius Kantor et al., 2018 and the hymenopteran genus Okutanius D.R. Smith, 1981.

Takashius nom. nov. (Neogastropoda: Buccinoidea: Fasciolariidae), замещающее название для Okutanius Kantor et al., 2018 non D.R. Smith, 1981
Кантор Ю.И.; Федосов А.Э.; СНАЙДЕР М.А.; БУШЕ Ф.;
Keywords
Gastropoda; type series; taxonomy; synonymy; Neritidae;
Pages
pp. 61 -
68

The nominal species name “Theodoxus dniestroviensis” was commonly accepted as introduced by Put’ in 1972 for neritid snails occurring in the upper part of the Dniester River basin. Currently an earlier publication [Put’, 1957] has been found in which this name is established in accordance with the ICZN guidelines, so the dating should be amended to Put’, 1957.

The type series of Theodoxus dniestroviensis is apparently lost but the samples from the type locality were recently traced in the National Museum of Natural History of the National Academy of Sciences of Ukraine (Kiev). An illustrated comparison of topotypic specimens with other morphotypes of regional river nerites is provided. Given the variation in conchological characteristics observed among the specimens of Th. fluviatilis, we consider Th. dniestroviensis to range within its intraspecific variability. This makes Th. dniestroviensis a junior subjective synonym of Theodoxus fluviatilis (Linnaeus, 1758).

Название брюхоногого моллюска “Theodoxus dniestroviensis Put’, 1972” является младшим субъективным синонимом Th. fluviatilis (L., 1758): решение на основе изучения топотипов
Анистратенко О.Ю.; Дегтяренко Е.В.; Осипова Д.С.; Максименко Ю.В.; Анистратенко В.В.;
Keywords
terrestrial snail; introduced species; alien species; bioinvasion;
Pages
pp. 69 -
80

The first record of the eastern Mediterranean species Monacha claustralis in Western Ukraine is described, where it was found in one urban habitat of Lviv together with a conchologically similar Monacha cartusiana. Based on the results of our research and literature data, the reliability of some anatomical criteria that can be used to differentiate M. claustralis and M. cartusiana has been analyzed. A considerable variability in the length and shape of the vagina in M. cartusiana in Western Ukraine has been demonstrated, which may cause the erroneous identification of some specimens of this species as M. claustralis. The pattern of the present distribution of M. cartusiana in Western Ukraine are also characterized.

Monacha claustralis и M. cartusiana (Gastropoda, Hygromiidae) – два криптических вида антропохорных наземных моллюсков на западе Украины
Гураль-Сверлова Н.В.; Гураль Р.И.;
Keywords
Russian Maritime Territory; R/V Akademik Oparin;
Pages
pp. 81 -
84

Boreotrophon oparini sp. nov., found in the Sea of Japan, off Russian Maritime Territory, is described and illustrated. The type material was sampled at a depth of 40 m (holotype) and 110 m (paratype) during the 64th expedition of R/V Akademik Oparin. Boreotrophon oparini sp. nov. is compared with the sympatric B. candelabrum and other congeneric species.

Новый вид рода Boreotrophon P. Fischer, 1884 (Gastropoda, Muricidae, Pagodulinae) из Японского моря
Бондарев И.П.;
Keywords
SoJaBio Expedition; microgastropods; Alvania;
Pages
pp. 85 -
92

Examination of unsorted microgastropod samples collected during the joint Russia-German research “Sea of Japan Biodiversity Studies (SoJaBio) Expedition” in 2010 and preserved in the National Scientific Center of Marine Biology, Far Eastern Branch of the Russian Academy of Sciences, Vladivostok, resulted in the finding of six species of the family Rissoidae. Among them, “Alvanianihonkaiensis Hasegawa, 2014 is newly recorded both in Russian waters and on the northern slope of the Sea of Japan, and Punctulum reticulatum Golikov, 1986 was rediscovered for the first time since its original description. Geographical and vertical distributions of each species and their significance are updated and discussed.

Батиальные Rissoidae (Gastropoda: Rissooidea) российского дальневосточного побережья Японского моря, с переописанием Punctulum reticulatum Golikov, 1986
Хасегава К.;
Keywords
land molluscs; bioinvasion; invasive species; Eastern Europe;
Pages
pp. 93 -
98

New data on the records of synanthropic slug species of Limacus maculatus and Arion vulgaris in Belarus are analyzed. It is assumed that the penetration of these species into the territory of Belarus occurred from other parts of their modern range together with the imported goods.

Новые находки синантропных слизней Limacus maculatus и Arion vulgaris (Mollusca, Gastropoda, Stylommatophora) в Беларуси
Островский А.М.;
Keywords
fauna of the Caucasus; new species; Euomphalia aristata; genital anatomy;
Pages
pp. 99 -
104

The study of the anatomy of Euomphalia aristata from the Western Transcaucasia showed that these populations differ from other species of the genus and from the typical populations of E. aristata from the North Caucasus in anatomy of the genitalia. E. aristata in Transcaucasia is characterized by the separation of the distal parts of the male and female sections of the reproductive system, a long oviduct, a very short proximal part of the vagina, and the location of the vaginal appendages close to the mucous glands. In E. aristata from the North Caucasus (North Ossetia), the male and female parts of the genitals are not separated in the distal part, the oviduct is short, the proximal part of the vagina has an S-shaped bend, and the vaginal appendages are located at a noticeable distance from the mucous glands. On these grounds we distinguish E. aristata in Transcaucasia as a separate species.

E. aristata was described from the vicinities of Kislovodsk that is on the northern macro-slope of the Main Caucasian Ridge; therefore, the name E. aristata is applicable to the snails inhabiting this region. For molluscs living on the southern slopes of the Caucasus Range and further south, we propose the name Euomphalia schileykoi sp. nov.

Euomphalia schileykoi sp. nov. (Mollusca, Gastropoda, Helicidae) в Закавказье
Шиков Е.В.; Палатов Д.М.;
Keywords
bathyal; Arctic Ocean; sunken wood; reducing habitats;
Pages
pp. 105 -
109

This paper describes finding of 3 specimens of Skenea profunda (Friele, 1879) in the Arctic Basin from a depth of 3700-3800 The species had been previously reliably known only from the bathyal part of the North Atlantic and is confined to communities of sunken wood. This is the second finding of a taxon obligate for such habitats in the Arctic Ocean and confirms the assumption that there is a fauna associated with wood falls on the path of the Transpolar Drift Flow in the Central Arctic.

Skenea profunda (Vetigastropoda: Skeneidae) в центральной Арктике
Нехаев И.О.;
Keywords
synonymy; lectotype designation;
Pages
pp. 111 -
114

It is proposed to exclude Stenoplax lindholmii from the list of Japanese chiton species, which turned out to be a junior synonym of S. magdalenensis. Lectotype of Chiton lindholmii is designated.

Chiton lindholmii Schrenck, 1862 (Mollusca: Polyplacophora) – младший синоним Stenoplax magdalenensis (Hinds, 1845)
Сиренко Б.И.; Сайто Х.;
Keywords
new species; anatomy;
Pages
pp. 115 -
120

One more tiny chiton of the genus Leptochiton is described from the shallow water of the Persian Gulf. The new species Leptochiton persianus sp. n. differs from other species of the genus living on coral reefs in shape of the tail valve with subcentral mucro, long central and first lateral teeth of radula, and round median denticle of the head of the major lateral tooth.

Новый крошечный хитон (Mollusca: Polyplacophora) из Персидского залива  
Сиренко Б.И. ;
Keywords
species distribution models; SDM; ecological modelling; environmental predictors; Black Sea region; biological invasions;
Pages
pp. 121 -
136

The terrestrial snails Brephulopsis cylindrica and Xeropicta derbentina are native to steppes of the Northern Black Sea region and; X. derbentina has also initially inhabited Eastern Mediterranean, the Caucasus, and Anatolia. However, in last decades the species are increasingly reported outside of their natural range which renders them as likely invasive. The paper aims to assess the ecological suitability of adjacent habitats in terms of the molluscs invasion. We address this using species distribution modelling (SDM). The selected environment predictors for SDM included 22 environment factors such as land cover, enhanced vegetation index (EVI), altitude, and 19 bioclimatic parameters. This suggests that the area with maximum suitability extends from the natural range to the Central Danube lowland in the West and up to the Volga Upland in the Northeast. These regions have similar EVI and are largely croplands. Among the predictors, the minimum temperature of the coldest month has the greatest impact on the modelling results, which agrees with the variable being the limiting factor for the distribution of subtropical invertebrates. The study reinforces the notions that X. derbentina and B. cylindrica are likely to further expand the boundaries of their range thus posing threats to native ecosystems.

Моделирование распространения наземных моллюсков-вселенцев Brephulopsis cylindrica and Xeropicta derbentina (Gastropoda: Stylommatophora)
Адамова В.В.; Орлов М.А.; Шелудков А.В.;
Keywords
Chukchi Sea; East Kamchatka; Commander Islands; Propebela fidicula; Propebela bogdanovi;
Pages
pp. 1 -
6

In 1990 I.P. Bogdanov provided the new localities for Propebela fidicula – off the Wrangel Island in the Chukchi Sea and off the eastern coast of Kamchatka [Bogdanov, 1990]. These locations were far beyond the known range of this species – from Puget Sound Bay to the Aleutian Islands [Oldroyd, 1927]. Verification of material from the ZIN collection showed that the real Propebela fidicula in Russian waters is found only near the Commander Islands. The shells that Bogdanov identified as Propebela fidicula, belong to a new species. It differs from Propebela fidicula both in sculpture and radular morphology.

Propebela bogdanovi sp. nov. (Gastropoda, Conoidea, Mangeliidae) – новый вид из Чукотского моря и с восточного побережья Камчатки
Меркульев А.В. ;
Keywords
Sibirivalvata; fauna; distribution; ecology;
Pages
pp. 7 -
19

The fauna of the rivers of the north of Western Siberia that do not belong to the Ob’ River basin is of particular interest from the point of view of zoogeography and understanding of the processes of formation of the freshwater malacofauna. Starting in the taiga zone, these rivers flow north and cannot serve as a way of interzonal dispersal of species from lower latitudes. However, information about the fresh-water malacofauna of these river basins is poorly presented in the scientific literature, some of the published species findings are doubtful or erroneous. The gastropod mollusks of the family Valvatidae of the Taz river basin (Western Siberia) are considered. The basin is located closer to the Yenisei than to the Ob’ River basin. The study was based on original authors’ material represented by both qualitative and quantitative samples. It has been found that eight species of mollusks of the genus Valvata occurs in the water reservoirs and streams of the Taz basin, an annotated list of species is presented, and a brief zoogeographic characteristic is given. Three species (Valvata helicoidea, V. sorensis and V. korotnevi) are for the first time recorded from the basin, one of them (V. korotnevi) is for the first time recorded from the Western Siberia waterbodies.

Моллюски семейства Valvatidae Gray, 1840 (Gastropoda, Heterobranchia) бассейна реки Таз (Западная Сибирь)
Андреева С.И.; Андреев Н.И.; Бабушкин Е.С.;
Keywords
taxonomy; Stemmatopsis; new species; Vietnam; Laos;
Pages
pp. 21 -
25

The terrestrial snail genus Stemmatopsis is mainly distributed in northern Vietnam and northern Laos. In total five species of Stemmatopsis are discovered, including two described herein. Stemmatopsis arcuatolabris sp. nov. has a small distorted-ovate shell with last whorl protruded quite strongly from ventral side. It has a thickened, expanded peristome with bended palatal side having a bow-like shape. Stemmatopsis dolium sp. nov., has a small, oblique-ovate shell, an approximately quadrangular aperture, and a wave-like shape at the palatal side of peristome.

Два новых вида рода Stemmatopsis J. Mabille, 1887 (Gastropoda: Stylommatophora: Streptaxidae) из Вьетнама и Лаоса
До Д.С.;