Harmozica zangezurica (Gastropoda, Pulmonata, Hygromiidae) - a cryptic species of land molluscs from southern Armenia

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.

Cornu aspersum (Gastropoda: Helicidae) in Western Ukraine with an overview of introduced species of land molluscs from this area

The first findings of Cornu aspersum in the Lviv region are described, including the shell size and shell colouration variability. A review of the known records of C. aspersum in different regions of Ukraine, from the second half of the 19th century to the present day, is also presented. The most probable ways of penetration and the possibility of further acclimatization of this species in Western Ukraine are discussed. The chronology of the records of introduced species of land molluscs in Western Ukraine is described in tabular form, which, to a large extent, should reflect the chronology of their penetration into this area. It is noted that the majority of alien species began to be found in Western Ukraine only at the end of the 20th or the beginning of the 21st century. Simultaneously several species appeared here, previously known only for the south of the country.

Spatial differentiation of land mollusc fauna in plain territories of Ukraine

The taxonomic and ecological composition of the autochthonous land mollusc fauna in different parts of the plain Ukraine was analyzed on the basis of the personal data, collection materials of the State Museum of Natural History of the NAS of Ukraine in Lviv as well as numerous literature sources. Excluding representatives of the genus Helicopsis, the taxonomy and species composition of which in the territory of Ukraine still require clarification, and the steppe part of the Crimean peninsula, in four landscape zones of Ukraine, currently, a total of 109 species of land molluscs, which are autochthonous for at least part of the analyzed territory, are registered. The maximum species diversity (103 species and 2 representatives of the genus Helicopsis) is recorded in the zone of deciduous forests, followed by the right-bank part of the forest-steppe zone. The smallest number of the autochthonous species of land molluscs was noted for the right-bank part of the steppe zone. Within the Ukrainian Polesie and the forest-steppe zone of Ukraine, the taxonomic diversity of land molluscs decreases from west to east. The number of the registered autochthonous species decreases, respectively, by 1.5 and 1.7 times, and the generic diversity by 1.3 and 1.5 times. In the steppe zone, the main centre of the species diversity is the Donetsk Upland, located in the east of the country. In taxonomic and ecological composition, land mollusc complexes of the right-bank part of the forest-steppe zone are closer to the zone of deciduous forests, in its left-bank part – to the left-bank steppe. In general, the spatial differentiation of land mollusc fauna in the plain territories of Ukraine is more strongly associated not with the boundaries of landscaped zones, but with the location of these territories with respect to the Dnieper bed and with some uplands, where the species diversity of land molluscs of the zone of deciduous forests and forest-steppe zone (Podolian Upland) and the steppe zone (Donetsk Upland) is concentrated.

A new aestivation strategy for land molluscs: hanging upside down like bats

Introduction: Many land molluscs survival strategies are still poorly understood or have not been even reported, especially in the Neotropics. Methods: I collected 25 adult Tikoconus (Tikoconus) costarricanus from Reserva Forestal Río Macho, Costa Rica. I kept the specimens for 8 days in terrariums to film their behavior. Objective: To analyse the behavior of T. costarricanus, with emphasis on its strategies to survive drought and probably also predation. Results: This snail has at least three unusual behaviors that probably help them reduce dehydration and may be escape from enemies and avoid diseases: hanging upside down like bats, falling and grooming. During aestivation, they compress the body and hang upside down from leaves, like bats hang from perches. They attach to the underside of leaves with mucus from a caudal gland. Disengagement is done with vigorous shell rotations and foot twisting in contorting sequences, and can be done as reaction to direct sunlight, and probably to avoid predators and parasites. They groom their own shell, shell lappets and foot, an unusual behavior among land snails. This species feeds mainly on epiphyllous mosses, algae and lichens, occasionally adding arthropod eggs and carrion. Egg laying is similar to other euconulids and valloniid snails. Conclusions: Aestivating hanging upside down is a drought avoiding trait described here for the first time and is also a new function for the caudal gland mucus. Leaf detaching is done by a contortion sequence of shell rotations and foot twisting; its complexity and duration varies according to the leaf side where the snail is located.

Anthropochorous species of land molluscs in Western Ukraine

The data on the recent distribution of 19 anthropochorous species of the land molluscs in Western Ukraine, which may become the basis for monitoring their further resettlement in the region, are summarized. For the first time the presence of the Balkan species Tandonia kusceri and the Crimean species Monacha fruticola in Western Ukraine is mentioned.

The land malacofauna from Vesuvius National Park and neighbouring areas (Naples, Southern Italy): Preliminary results

The faunistic data on the recent land molluscs of Vesuvius National Park (Naples, Southern Italy) and neighbouring areas sampled during field surveys from 2005 to 2006 are reported here. The data were obtained through a careful research on museum collections and literature and were supplemented with observations from field surveys. Up to now, only 23 land snails species were known from the Vesuvius National Park through bibliographical data. The faunistic research, carried out in 25 stations of different environment typologies, allowed us to discriminate 31 species: 15 of these species are reported here for the first time for the study area. The presence of 16 species was confirmed by other field investigations. Other 19 taxa are reported in the literature, but not confirmed in our research - Helix turriculatella O. G. Costa, 1839 (obsolete nomenclature), Trochoidea trochoides Poiret, 1789, Hygromia cinctella (Draparnaud, 1801), Campylaea planospira (Lamarck, 1822), Vitrea sp. (cf. contracta (Westerlund, 1871)), Cecilioides acicula (O. F. Müller, 1774), Cochlicella acuta (O. F. Müller, 1774), Theba pisana O. F. Müller, 1774). Another 12 taxa are highly doubtful, because of possibilities for confusion with species living in other European or Italian regions, as well as previous misidentifications (Deroceras agreste (Linnaeus, 1758), Monacha gregaria (Rossmässler, 1839), Cochlicella barbara (Linnaeus, 1758), Monachoides incarnatus (O. F. Müller, 1774),Cernuella (Cernuella) cisalpina (Rossmässler, 1837), Cernuella aradasii (Pirajno, 1842), Oxychilus cellarius (O. F. Müller, 1774), O. alliarius (J. S. Miller, 1822), Zonitoides nitidus (O.F. Müller, 1774), Hyalina pseudohydatina, Ferussacia lubrica, Aegopinella nitens (Michaud, 1831); it was impossible in these cases to refer to their current specific name. Eobania vermiculata (O. F. Müller, 1774), Rumina decollata (Linnaeus, 1758), Papillifera papillaris (O. F. Müller, 1774) appear to be the most common species. Interesting are the records of Marmorana muralis (O.F. Müller, 1774), Helix cf. ligata (O.F. Müller, 1774) and Charpentiera gibbula gibbula (Rossmässler, 1836). Charpentieria gibbula honii (Tiberi, 1878) needs genetic investigations in order to confirm its taxonomic status. One allochthonous species (Paralaoma servilis (Shuttleworth, 1852)) was surveyed for the first time in the study area. A Red List of Threatened Species is proposed and the species are classified according to the IUCN criteria (Version 2019-2.1). The malacofauna of Vesuvius - Somma Mountain Complex is composed by 38 land mollusc species and represents 36.2% of the total species present in Campania (about 105 species, personal data) and 12.8% of the Italian fauna (about 530 species of land molluscs extrapolated from the list of Bank (2017). It is assumed that the poor biodiversity of the Vesuvian land malacofauna can be attributed essentially to the scarcity of calcareous substrates and the absence of permanent water sources.

SHELLS OF MOLLUSCS FROM MOTORONYN HILLFORT

The shells of 3 land molluscs’ species are found in the historical layer of VI—V century B.C. from the Motronyn hillfort of the Scythian age (Chyhyryn district of Cherkasy region, Ukraine): Helix pomatia, Austrotachea vindobonensis and Fruticicola fruticum. All these species are known to still occur in this area. Since it was disputable whether the H. pomatia was recently introduced in the Dnipro area, an evidence of its presence for at least 2400 years in this region is notable. Nature of damage to the shell of H. pomatia indicates that it was probably used for food by humans.