In the field of zoological (and palaeontological) research, accurate documentation methods for the exo-morphology are essential. Here we propose a new method for the documentation of cephalopod paralarvae and juveniles. For documenting small-sized cephalopods autofluorescence microscopy offers numerous advantages for the presentation of outer body parts and surface structures in high resolution, partially also of internal structures such as the gladius. Structures are especially well-contrasted compared to other imaging methods, such as white-light microscopy, micro- or macrophotography. This facilitates a detailed view in high resolution at even the smallest cephalopod paralarvae. Autofluorescence imaging, combined with composite imaging, creates sharp, evenly illuminated pictures. In its higher magnification ranges it can be well compared to low-magnifying scanning electron microscopy (SEM) images, but with the advantage that the drying, mounting and preparation needed for SEM is not necessary for autofluorescence microscopy. In contrast the method enables the direct documentation of specimens inside their storage liquid. This is especially important for the investigation of rare specimens, e.g., for historical material from museum collections, or as a pre-documentation for specimens that will be processed further with an invasive method. By the use of different excitation wavelengths it is furthermore possible to either enhance surface structure details or certain inner body structures. Autofluorescence microscopy is also excellent for the imaging of certain types of small-sized fossil cephalopods, not least as the contrast against the matrix can be significantly improved. All these methods and the associated opportunities for studying cephalopod paralarvae are explored in this study.

Son La is a province in the north-western Vietnam, the mountain chain running along the Northwest-Southeast has a phylogenetically diverse terrestrial snail fauna dominated by endemic species, which are very little known so far. This is the first checklist of the terrestrial prosobranch snails from Son La. It includes 42 species, belonging to 17 genera in five families, of which three species are endemic (Dioryx vanbuensis, Cyclophorus implicatus, and Scabrina vanbuensis). In this study two species are recorded for the first time for Vietnam (Chamalycaeus paviei, Scabrina laciniana) and 32 additional species are added to the species list of the Son La.

In 1881 expedition of the Bremen Geographical Society collected molluscs in the north-western part of the Bering Sea off the coast of Chukotka. Unfortunately, the result of this work has not been fully appreciated by Russian malacologists since it was believed that the German expedition was working in American, not Asian waters. In this paper, On the basis of materials from the collection of the Berlin Museum of Natural History and published data it is proved, that molluscs were collected off Asian coast. Photos of the types of Gastropoda described A. Krause, are presented for the first time. "Bela" luetkeana Krause, 1885 (Mangeliidae) is attributed herein to the genus Propebela Iredale, 1918.

A new species of chiton, Leptochiton antarcticus n. sp., is described from the Southern Ocean from depths of 87-1,524 m. The new species is distinguishable from other congeneric species by the shape of head of major lateral teeth of radula, dorsal scales and anterior position of mucro.

The patterns of the migration activity of 43 species of land snails and slugs were analyzed on the basis of both original and literature data. Different species of terrestrial mollusks demonstrate significant intra- and interspecific differences in their migratory abilities. During short-term experiments, the distance from release point was determined mainly by displacement of individuals by random (Brownian) motion. Random events of passive dispersal of the snails (homing) were observed in the course of the long-term experiments lasting several years. The possibility of passive dispersal of terrestrial mollusks by means of different mechanisms (anemochory, hydrochory, zoochory and anthropochory) has been shown. Two distinct spatial scales in the process of the terrestrial mollusks invasion (transcontinental and intra-continental) were distinguished. Most cases of transcontinental invasion represent mainly the transfer of European species to Africa, North and South America, and Australia.

The data on distribution of molluscs of the genus Digyrcidum Locard, 1882 in waterbodies of the Urals and Western Siberia are given. A new species, Digyrcidum starobogatovi Andreeva et Lazutkina, sp. nov., is described. This species inhabits waterbodies of the Urals and Western Siberia cojointly with the species Digyrcidum bouguirgnati (Paladilhe, 1869).

It is established that all reports of Oxychilus diaphanellus outside of Crimea were based on an erroneous identification of Oxychilus translucidus. The differences between these two species, as well as those between O. translucidus and some other species of Oxychilinae in Ukraine, are discussed.

The present investigation was undertaken to study a shell disease of the freshwater snail, Pila globosa. Observations were made in June-July in four consecutive years. The disease first appears as blisters in the periostracum and then, once the periostracum is lost from these lesions, dissolution of the underlying calcified layer. The numerically predominant bacterial genera in the lesions included Aeromonas, Pseudomonas, Escherichia and Listeria. Communication describes this previously unreported shell disease, which may be a health problem in apple snails.

Lymnaea (Stagnicola) likharevi Lazareva, 1967 and Lymnaea (Stagnicola) saridalensis Mozley, 1934 – two closely allied lymnaeid species that inhabit Western Siberia and, in many cases, may co-occur in the same habitat. A detailed study of conchological and anatomical variation of the two species from seven syntopic samples has shown that these are non-diagnosable since there is no morphological hiatus to separate them. A new synonymy is established: L. likharevi is a junior synonym of L. saridalensis. The data on the type series of the studied species as well of Lymnaea draveri Mozley, 1934 are provided.

Several species of freshwater snails are for the first time registered from the waterbodies of the central part European Russia (Moscow Region and adjacent areas) based upon own author’s samplings and museum collections. These are: Lymnaea (Corvusiana) corvus (Gmelin, 1791), Lymnaea (Corvusiana) gueretiniana (Servain, 1881), L. (S.) archangelica Kruglov et Starobogatov, 1986, L. (S.) fusca (C. Pfeiffer, 1821) sensu Kruglov, 2005, L. (S.) callomphala (Servain, 1881), L. (Peregriana) fulva (Küster, 1862), Anisus (Costorbis) strauchianus (Clessin, 1886), Physa taslei Bourguignat, 1862, and Pseudosphaerium pseudosphaerium (Favre, 1927). The data on their ecology and distribution in the region are given alongside with diagnostic characters, taxonomic and nomenclatorial remarks. This newly obtained information is useful for more exact zoogeographical characterization of the region. It has been shown that the malacofauna of the upper Volgian drainage basin is, possibly, not so zoogeographically peculiar as it was considered earlier.

Leptochiton muelleri Sirenko and Schwabe ( 2011) was known from only 7 specimens found near Sri Lanka. The author in 2010-2014 in Vietnamese waters collected the species from South to North Vietnam. Leptochiton muelleri turned out to be a very wide spread Vietnamese species, found from Con Dao Id. (08º39’N) to Van Don (21º02’N). This minute species was found by using a new method of collecting, described by Sirenko (2012). It is expected that the species will have a wide distribution into the Indo West Pacific Region.

Annotated check-list of shell-bearing Gastropoda of Murman Coast (Barents Sea Coast of Kola Peninsula) is presented. Based on original material collected in 1996-2013 and literature data 148 species are recorded for the region. Nine species: Skenea rugulosa (G.O. Sars, 1878), Aclis sarsi Dautzenberg et Fischer, 1912, Admete clivicola Høisæter, 2010, Nassarius incrassatus (Strøm, 1768), Raphitoma leufroyi (Michaud, 1828), Taranis moerchi (Malm, 1861), Ondina divisa (J. Adams, 1797), Menestho albula (Fabricius, 1780), Bogasonia volutoides Warén, 1989 were absent in previous reviews of Russian molluscan fauna. Three species with unclear taxonomical position are listed: Skenea cf. trochoides, Omalogyra cf. atomus and Chrysallida sp. A majority of species found in Murman waters have a boreal distribution and are typical for northern European fauna. References to previous studies based on material from Murman Coast as well as original records are listed for each species, some remarkable species are depicted and discussed.

A comparative analysis of the camera eyes of gastropod pulmonate mollusks Trochulus hispidus (Linnaeus, 1758) from the South Sweden and Kaliningrad Region was carried out on the basis of own and published data. It was demonstrated that the mollusks’ eyes have common structure but different size, and their principle components have more similarities in morphological and optical properties than in anatomical parameters.

The genus Retifusus was revised on the basis of conchological characters, radular morphology, foregut and stomach anatomy. Ten previously described and one new species are recognized as valid: R. jessoensis (Schrenck, 1863 in 1862-63), R. virens (Dall, 1877), R. olivaceus (Bartsch, 1929), R. laticingulatus (Golikov et Gulbin, 1977), R. roseus (Dall, 1877), R. parvus (Tiba, 1981), R. attenuatus (Golikov et Gulbin, 1977), R. similis (Golikov et Gulbin, 1977), R. iturupus (Golikov et Sirenko, 1998), R. latericeus (Möller, 1842), and R. latiplicatus sp. nov. Chrysodomus brunneus Dall, 1877 was synonymized with R. jessoensis; Bela yanamii Yokoyama, 1926 – with R. virens; Plicifusus saginatus Tiba, 1980 and Retifusus semiplicatus Golikov in Golikov et Scarlato, 1985 – with R. parvus.

The article contains additional data on the structure of the penial papillae and the atrial stimulators of the representatives of 13 species and subspecies of 8 (sub)genera of Ariantinae. The existence within the subfamily of five or six variants of structure of the copulative apparatus has been shown. Papilla of the penis or its elements can take on the role of stimulator; in such cases stimulator mostly is reduced down to full disappearance. Reproductive tract of some species has been re-described.

The genus Aulacofusus Dall, 1918 has been revised on the basis of conchological and available anatomical data. Nine previously described Recent species and one subspecies are recognised as valid: A. brevicauda (Deshayes, 1832), A. periscelidus (Dall, 1891), A. herendeeni (Dall, 1899), A. esychus esychus (Dall, 1907), A. esychus shikotanicus (Golikov et Gulbin, 1977), A. ombronius (Dall, 1919), A. calathus Dall, 1919, A. coerulescens Kuroda & Habe, 1961, A. hiranoi (Shikama, 1962), A. calamaeus (Dall, 1907). A. gulbini sp. n. is described, A. brevicauda fortilirata (Sowerby, 1913) has been synonymized with A. periscelidus (Dall, 1891). For 6 species, detailed descriptions of anatomy are provided. Twenty three species previously referred to Aulacofusus, have been excluded from the genus.

New findings of three gastropod species in Russian waters are discussed. Both Gibbula cineraria and Pseudosetia turgida were previously reported in Russian faunistic literature but absent in recent one. Haliella stenostoma is reported for the first time from Russian waters. Brief species descriptions are provided.

The problem of generic classification of the basommatophoran family Lymnaeidae Rafinesque, 1815 is reviewed as well as recent theoretical approaches to genus delineation in the zoological systematics. Two main versions of the generic system of lymnaeid snails are: 1) bigeneric approach where all diversity of lymnaeid species is split between two genera; and 2) polygeneric approach suggesting that there are several (about twenty) genera in the family. The first version is presented in systems developed by Kruglov and Starobogatov [1993] and Jackiewicz [1993, 1998]. The second one is most commonly accepted in current Western European and Northern American literature [Burch, 1989; Falkner et al., 2001; Glöer, 2002]. However, there are no grounds to delimit lymnaeid genera objectively as the solution critically depends on what taxonomic methodology (cladistic or ‘evolutionary’ taxonomy) is followed by a particular author. The ‘evolutionary’ taxonomic methodology (sensu Mayr) is favorable to the bigeneric approach, whereas the cladistic (Hennigian) methodology leads to the separation of a series of taxa of generic rank within Lymnaeidae. It is impossible to prefer one approach to another ultimately since the problem of acceptability of paraphyletic taxa is still not resolved. The co-existence of two different generic systems of the same family is therefore inevitable. Different criteria of generic rank were critically discussed in perspective of their applicability to lymnaeid taxonomy. The morphological and ecological criteria as well as the criterion of hybridizability proved to be controversial and their use gives no key to select one of these approaches. The fourth criterion, that of monophyly, is more usable now, when the data of molecular phylogenetics are available. The recent advances in molecular taxonomy of pond snails have been reviewed briefly. It seems very reliable that the family consists of two large monophyletic clades of deep origin that differ from each other by chromosome number albeit there are no morphological characters to distinguish surely between representatives of these clades. It is impracticable to assign the generic rank for these clades due to their huge internal heterogeneity (morphological and ecological). The most reliable cladistic solution is to regard the two deep lymnaeid clades as separate subfamilies each containing a set of genera that are internally homogeneous enough to comply with most of criteria of the genus rank. The scheme of lymnaeid classification proposed here includes the nominotypical subfamily Lymnaeinae (type genus Lymnaea Lamarck, 1799) with haploid chromosome number equal to 18 (rarely 19), and the new one Radicinae subfam.n. (type genus Radix Montfort, 1810). The latter taxon embraces genera and species of Lymnaeidae characterized by 16 or (most often) 17 chromosome pairs. Radicinae is, most probably, derived clade as compared to Lymnaeinae, however, there are no morphological synapomorphies to support it. The bigeneric system is, however, still acceptable for those who uses generic criteria proposed by “evolutionary systematics” such as “principle of the same degree of difference” [Golikov, Starobogatov, 1988] and others.

New investigations of freshwater habitats in caves revealed five new species of the Rissooidea in Bulgaria. The new species: Belgrandiella maarensis n. sp., Pontobelgrandiella tanevi n. sp. (the second species from this genus ever known), Bythiospeum simovi n. sp., Bythiospeum kolevi n. sp., Bythiospeum stoyanovi n. sp. are described and types illustrated. A synopsis of all published data on this ecological gastropod group in the country was compliled and complemented by author's unpublished data to provide a catalogue of all known Bulgarian stygobiotic and troglophilous freshwater snails with their localities.

A detail description of the shell and reproductive system of Elia novorossica is given and illustrated. The populations of this species on the Donetsk Upland in Ukraine are established as a new subspecies – E. novorossica nagolnica subsp. nov. Distribution and habitats of this subspecies are described in detail. Three populations of E. novorossica are currently known on Donetsk Upland, one of which is discovered for the first time. All these populations inhabit oak forests along the small rivers in the basin of the Nagolna river, in the highest part of upland. A conservation status of E. novorossica in Ukraine is considered as critically endangered, which is true for the new subspecies on the global level. Species composition of terrestrial molluscs in the locations of E.novorossica and on adjacent territories is adduced.