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Contrary to insects, snails only rarely become embedded in amber. Snail inclusions dealt with in this paper come from Baltic amber: five represent species described at the end of the 19th c., whose status has now been revised, two are of uncertain position, one is a Leiostyla - a genus not previosly found in amber, and one - Propupa hoffeinsorum gen. and sp. nov., with its unique apertural barriers - may prove an important link in further studies on the origin, evolution and distribution of pupilloids. Reasons for the rarity of snail inclusions and geographical affinities of the Baltic amber snails are discussed. A catalogue of Baltic amber snails is provided.
Selected life-cycle and population parameters of a common Euro-Siberian wetland snail – Succinea putris (L.) – were studied in the field and in the laboratory. In the field the snails reproduced at least from April till September, with April–May and August–September peaks; only one such peak (April) was observed in the laboratory, though the snails reproduced throughout the year. The changes in population size structure in the field and the laboratory results (life span 210–420 days, mean 309) indicated semelparity. Growth in the laboratory included two phases: slow (November–March) and fast (June–October); which phase came first during the life cycle depended on the date of hatching. The growth rate in the field corresponded closely with the fast-phase growth in the laboratory. The smallest reproducing individual was slightly over 2.8 whorls; snails of 3.0 whorls were regularly observed to produce eggs (maximum number of whorls in adults: 4.0). Sexual maturity was attained in ca. 160 days. The eggs (non-calcified, translucent, spherical, 1.7–2.0 mm in diameter) were laid in batches, 5–64 per batch; the eggs within a batch were glued together. The batch dimensions were 3.5–25.7×2.2–24.7 mm. The time to lay a batch was 20–35 minutes. Forty-eight snails produced 74 batches within 12 months. The duration of the egg phase was 11–28 days, which might indicate egg retention of varied duration; hatching was asynchronous, spanning 1–12 days within a batch. The hatchlings had shells of 1.1–1.2 whorls; hatching success was 95%. Neither uniparental reproduction, nor egg or juvenile cannibalism were observed. When compared to data in the literature, our results imply that Succinea putris displays substantial local variation in life-cycle traits.We also provide an overview table to discuss similarities and adaptive radiation in the European succineid species.
The second site of Pupilla alpicola (Charpentier) was found in Poland in 2010. It is a treeless alkaline fen located close to the village of Czarny Dunajec (Nowy Targ region, S. Poland). The site is the north-western extension of the Western Carpathian distribution of the species, being more than 30 km away from the previously known Polish site near Niedzica village and also from its known sites in Slovakia. The first recent record of Pupilla pratensis (Clessin) in Poland was found in the north-eastern most part of Poland close to the border with Lithuania, in the vicinity of the village of Rowele. It is an extension of the species' distribution in NW. Europe and also the eastern most known record of this taxon. Both species are exclusive inhabitants of calcareous fensand fen meadows, highly endangered and mostly isolated, and deserve attention of nature conservation agencies.They seem to be very rare in Poland, because no further population was documented at 25 suitable alkaline fen sites sampled mainly in 2010 and 2011 across the southern and eastern part of Poland.
Based on over 3,500 dry shells and alcohol-preserved specimens from 77 localities, new records of 12 species (Truncatellina callicratis (Scacchi), T. himalayana (Benson), Boysia boysii (L. Pfeiffer), Vertigo antivertigo (Draparnaud), V. pseudosubstriata Ložek, Gastrocopta avanica (Benson), G. huttoniana (Benson), G. klunzingeri (Jickeli), Pupilla muscorum (Linnaeus), P. annandalei Pilsbry, P. turcmenica (O. Boettger), P. signata (Mousson)) are given; ten species (Columella nyrnphaepratensis sp. nov., Truncatellina ayubiana sp. nov., T. babusarica sp. nov., Vertigo superstriata sp. nov., V. nangaparbatensis sp. nov., Boysidia tamtouriana sp. nov., Papilla khunjerabica sp. nov., P. satparanica sp. nov., P. ziaratana sp. nov., P. paraturcmenica sp. nov.) are described. Shell variation is discussed for most species; the reproductive system is described and illustrated for nine species. Northern Pakistan, with its broader altitudinal range and generally wetter environmental conditions, has the highest diversity of pupilloids belonging to the genera discussed herein. Of the 22 species discussed in this report, ten species are currently considered endemic to Pakistan, the other 12 species being known from elsewhere in the region (Asia, Europe, and the Holarctic). The pupilloid fauna displays a high degree of Palaearctic/Holarctic influence at the generic level.
The aim of our study was to assess the small scale distribution (up to several m²) of hibernating forest-dwelling snails in relation to small-scale environmental factors, like litter composition, soil temperature and humidity or vegetation cover. The study was conducted in the ”Dębno nad Wartą” (local name) natural reserve, western Poland, in December 2006. A novel, cartographic method was applied for analysing and illustrating the small-scale distribution and habitat preferences of the snails. Four permanent study plots (15 m²) were established in 50 m intervals. Each plot was divided in fifteen 1m² squares, and from each square a litter sample was taken and analysed (60 samples in total). 17 snail species were recorded (6–13 species per plot; 0–8 per square). The distribution of particular species was clustered as its coefficients of variation were high (CV%> 150) as well as was the small-scale distribution of the total abundance of all the species (CV% = 122). The most uniformly distributed and frequent (C% of all samples) species were Trichia hispida (Linnaeus) (CV%= 153; C% = 45), Cochlodina laminata (Montagu) (206; 30) and Perforatella incarnata (O.F. Müller)(152; 37). Among frequent species the greatest value of CV% (425) and therefore the most patchy distribution was recorded for Ruthenica filograna (Rossmässler). According to the results of CCA, this species, together with Vitrina pellucida (O.F. Müller) (CV% = 296), and Clausilia bidentata (Ström) (CV% = 291), were the most stenotopic, wintering in specific microhabitats with low herb layer coverage, elm leaves prevailing in the litter and high percentages of hornbeam, ash, birch and alder leaves. In turn, for Perforatella rubiginosa (A. Shmidt) (CV% = 440) and Perforatella bidentata (Gmelin)(CV% = 440), also the species with patchy distribution – optimal wintering conditions were found in places with a higher soil temperature and the litter consisting mainly of oak leaves. The remaining snail species seem to be more eurytopic and winter in microhabitats with intermediate conditions. The results of the present study show that for the distribution of majority of species studied the most important factor is the proportion between the coverage of litter and herbaceous vegetation cover. The species richness of the malacocenoses studied strongly depends on the diversity of litter, since particular species prefer leaves of different trees.
The paper presents data on 10 terrestrial snail species: Platyla polita (W. Hartmann, 1840), Carychium (Carychium) minimum O. F. Müller, 1774, C. (Saraphia) tridentatum (Risso, 1826), Succinea putris (Linnaeus, 1758), Succinella oblonga (Draparnaud, 1801), Oxyloma (Oxyloma) elegans (Risso, 1826), O. (O.) sarsii (Esmark, 1886), Cochlicopa lubrica (O. F. Müller, 1774), C. lubricella (Rossmässler, 1834), C. nitens (M. von Gallenstein, 1848), recorded over the last fifty years in the Wielkopolska district (W. Poland). They include species location in the UTM grid on the map of Wielkopolska. Among those species Cochlicopa lubrica (663 sites) and Succinea putris (422 sites) are the most frequent in Wielkopolska.
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