Volume 30

Volume 30 part 2

Keywords
microvilli; cilia; Caenogastropoda;
Pages
pp. 93 -
101

Cellular composition and morphology of components of photoreceptor apparatus of the retinae of camera eyes of some species of terrestrial gastropod pulmonate molluscs were studied and its evolutionary transformations were traced. It was demonstrated that all examined characteristics of photoreceptor apparatus of the most investigated species were normal for terrestrial pulmonates, while those of one species were special. Evolutionary transformations of photoreceptor apparatus of terrestrial pulmonate molluscs due to habitat shift were quite significant and concerned of its cellular composition and morphology of photoreceptor cells.

Клеточный состав, морфологическая характеристика и эволюционные изменения фоторецепторного аппарата камерных глаз наземных брюхоногих моллюсков (Heterobranchia, Stylommatophora)
Шепелева И.П.;
Keywords
intraspecific; polymorphism; quantitative indicators; thickness; valves; weight;
Pages
pp. 103 -
113

The morphological variability of the bivalve mollusc Flexopecten glaber was studied based on the analysis of 306 specimens from the Kazach’ya Bay (Sevastopol, Crimea) of the Black Sea. The sampling of mollusks was carried out with the help of skuba equipment in June–September of 2017–2018. For F. glaber, the age and size characteristics are given and the main trends in their ratios with the shell growth are considered. For the first time, quantitative indicators of thickness of the shell valves, their weight and height of the radial ribs are presented and discussed. A wide intraspecific polymorphism of the shell is shown in a relatively narrow range of habitat conditions. The obtained data expand the understanding of the morphological variability of F. glaber in the Black Sea and provide new information on the functional morphology of the species.

Новые данные о морфологической изменчивости раковины Flexopecten glaber (Linnaeus, 1758) (Bivalvia, Pectinidae) в Чёрном море
Бондарев И.П.;
Keywords
Fresh-water and brackish-water species; type series; diversity; taxonomy; nomenclature; Black Sea; Caspian Sea;
Pages
pp. 115 -
134

An illustrated overview of the type series of nominal taxa of the gastropod genus Theodoxus (Neritidae) inhabiting the Ponto-Caspian region is presented. It is made on the basis of a revision of large European malacological collections and includes descriptions of the type specimens of 16 taxa of different rank (species, variety, morph). Apart of these, the “type” specimens of four taxa with unavailable names have been traced in ZIN collection; we illustrate them to show the variability of Ponto-Caspian Theodoxus. In most cases, the photographs of the type specimens are published for the first time. We provide a taxonomic analysis of all studied type series, with comments on the nomenclature, systematic position and taxonomic rank of all nominal taxa of Theodoxus recorded from the Ponto-Caspian area.

Обзор видов рода Theodoxus (Gastropoda: Neritidae) Понто-Каспийского региона с рассмотрением доступного типового материала
Анистратенко В.В.; Ситникова Т.Я.; Кияшко П.В.; Винарский М.В.; Анистратенко О.Ю.;

Volume 30 part 3

Keywords
Bivalvia; Sphaeriidae; fauna; distribution; ecology; Urals;
Pages
pp. 135 -
147

The article is devoted to the fauna of Bivalvia (family Sphaeriidae) of waterbodies and watercourses of the eastern slope of the Polar and Pre-Polar Urals. The fauna of freshwater clams of this region remains practically unexplored. This study aimed at identification of the species content of Bivalvia and publication of images of their shells. We analyzed both qualitative and quantitative samples of molluscs as well as fish stomach contents. The identification of the material was based on conchological features, including the hinge structure. In total, 31 sphaeriid species is reported, and the annotated check-list, brief zoogeographic characteristics of the fauna, and shell images are provided. Most species demonstrate a limited spatial distribution within the studied area. The causes of discrepancies between published lists of sphaeriid species are discussed.

Материалы к фауне пресноводных двустворчатых моллюсков водоемов и водотоков восточного склона Полярного и Приполярного Урала
Андреева С.И.; Андреев Н.И.; Бабушкин Е.С.;;
Keywords
Phaedusinae; taxonomy; new species; Caucasus;
Pages
pp. 149 -
154

Pontophaedusa gregoi sp. nov. is described from the Imereti Region of Georgia. This is the second species of a Tertiary relict genus that represents a very early diverged lineage of the Phaedusinae subfamily. The differences between the shell characters and climatic preferences of the Pontophaedusa species are discussed.

Второй существующий вид рода Pontophaedusa Lindholm, 1924 (Gastropoda, Pulmonata, Clausiliidae) из Грузии
Мумладзе Л.; Секереш М.;
Hernández Quinta M.; Bauzá Hernández M.A.; Franke S.; Fernández Velázquez A.;
Keywords
Cepolidae;
Pages
pp. 155 -
164

A new genus and species of Cepolidae are described from the Island of Cuba: Plagiosimilis gibarensis gen. et sp. nov. It is classified in Cepolidae based on the following diagnostic characteristics of the family: dart apparatus consisting of a dart sac with a pedunculated gland on its apical side, both covered by a sheath; at the base of the dart apparatus there are two accessory glands; absence of a diverticulum. The specimens from the new genus come from the northern part of the Holguin province in the vicinity of the town of Gibara and live in special habitat dominated by Tillandsia plants. Shell with the rounded last whorl last very globular round, circular umbilicus and strongly reflected lip distinguish conchologically the new genus. The reproductive system and the shell differ from the other genera, although it have a certain similarity with the genera Plagioptycha and Hemitrochus.

Новый род и вид Cepolidae is Кубы (Pulmonata, Helicoidea)
Эрнандес Куинта М.; Бауза Эрнандес М. А.; Франке Ш.; Фернандес Веласкес А.;
Keywords
taxonomy; Dien Bien; Vietnam;
Pages
pp. 165 -
172

A report is given on the genus Rhiostoma (Cyclophoridae) collected in Vietnam during recent fieldwork. Locality data, Vietnam distribution and general distribution are given for each species, including references to previously published records. Five named species are listed, of which a new species is described, Rhiostoma ningbien sp. nov., from Dien Bien, North-western Vietnam.

Наземные моллюски рода Rhiostoma Benson, 1860 из Вьетнама (Gastropoda: Caenogastropoda: Cyclophoridae) с описанием нового вид
До Д.С.; Нгуен Т.С.; До Х.Л.;
Keywords
Septibranchia; Anomalodesmata; predaceous molluscs; morphology; new species;
Pages
pp. 173 -
182

The family Lyonsiellidae comprises carnivorous bivalve molluscs, distributed worldwide from sublittoral to ultraabyssal depths. One of the key anatomical characters of lyonsiellids is the reduction of the gill filaments in size and number and an increase of amount of muscles and connective tissue in gills, so their ctenidia represent an intermediate stage between eulamellibranch and septibranch conditions. The family Lyonsiellidae presently includes four genera: Lyonsiella, Allogramma, Policordia and Dallicordia. Taxonomy of the family is still problematic at both generic and species levels. The genus Dallicordia, typified by Lyonsiella alaskana was established on the assumption that it has no gills but possesses a muscular septum pierced by ostia, in contrast to the other lyonsiellids that have filamentous gills. Additionally, Lyonsiella uschakovi and Policordia ochotica were tentatively assigned to the new genus. Later P. ochotica was synonymized with P. media. In this paper we show that actually the Dallicordia was typified by an undescribed species misidentified as Lyonsiella alaskana which we describe here as D. bernardi sp. nov. Taxonomic position of the genus is dubious and could be clarified only after additional anatomical data on its type species becomes available. On the basis of examination of the type material of P. ochotica and images of the holotype of P. media, we reinstate the species P. ochotica. For the first time photographs of the holotype of L. uschakovi are provided for this specimen that was previously considered lost. Given the current state of knowledge we propose to consider species L. alaskana, L. uschakovi and P. ochotica in frame of the genus Policordia, for which we provide a list of all 29 species described up to date.

Статус рода Dallicordia и состав глубоководных хищных двустворчатых моллюсков рода Policordia (Bivalvia, Verticordioidea, Lyonsiellidae)
Сафонова Л.А.; Крылова Е.М.;

Volume 30 part 4

Keywords
Nudibranchia; Flabellinidae; Coryphellina; integrative taxonomy; species complex; cryptic species;
Pages
pp. 183 -
194

Flabellina rubrolineata was believed to have a wide distribution range, being reported from the Mediterranean Sea (non-native), the Red Sea, the Indian Ocean and adjacent seas, and the Indo-West Pacific and from Australia to Hawaii. In the present paper, we provide a redescription of Flabellina rubrolineata, based on specimens collected near the type locality of this species in the Red Sea. The morphology of this species was studied using anatomical dissections and scanning electron microscopy. To place this species in the phylogenetic framework and test the identity of other specimens of F. rubrolineata from the Indo-West Pacific we sequenced COI, H3, 16S and 28S gene fragments and obtained phylogenetic trees based on Bayesian and Maximum likelihood inferences. Our morphological and molecular results show a clear separation of F. rubrolineata from the Red Sea from its relatives in the Indo-West Pacific. We suggest that F. rubrolineata is restricted to only the Red Sea, the Arabian Sea and the Mediterranean Sea and to West Indian Ocean, while specimens from other regions belong to a complex of pseudocryptic species.

Молекулярно-генетический анализ и обновленное таксономическое переописание Flabellina rubrolineata (Nudibranсhia: Flabellinidae) из Красного и Аравийского морей
Екимова; И.А.; Антохина Т.И.; Щепетов Д.М.;
Keywords
Culcita novaeguineae; Linckia laevigata; symbiosis; parasitism; stable isotopes analysis; diet;
Pages
pp. 195 -
202

The trophic relationships between two species of symbiotic gall-forming molluscs from the genus Stilifer (family Eulimidae) and two of their hosts-asteroid species, Linckia laevigata and Culcita noveaguineae, were investigated using the stable isotope analysis of carbon and nitrogen. The aim of present study was to identify the most preferable host tissue in the symbionts’ diet. We analyzed δ15N and δ13C values in tube-feet, gonads and digestive glands of the hosts-starfishes and in muscles of the molluscs. Both symbiont species did not differ to each other both in δ15N and δ13C values. The average δ15N and δ13C values of Stilifer variabilis were significantly different from the digestive glands and gonads of their host Culcita novaeguineae and did not show differences from the tube-feet of starfishes. A similar pattern was found in the symbiotic association of Stilifer utinomi and Linckia laevigata. The tube-feet of analyzed starfishes had significantly higher average δ15N and δ13C values than the digestive glands and gonads. Obtained isotopic signatures indicate that symbionts do not feed on the host’s tissues, but take nutrients from their digestive system. It seems that the proboscis of Stilifer spp. absorbs the nutrients from the digestive system of the host-starfish thereby not disturbing significantly the host’s immune system.

Трофические взаимодействия между галлообразующими моллюсками рода Stilifer (Gast­ropoda, Eulimidae) и их хозяевами (Echinodermata)
Мехова Е.С.; Дгебуадзе П.Ю.;