Zierliche Tellerschnecke (Anisus Vorticulus)
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Anisus Vorticulus (Troschel 1834) (Gastropoda: Planorbidae) in Northeast Germany
JOURNAL OF CONCHOLOGY (2013), VOL.41, NO.3 389 SOME ECOLOGICAL PECULIARITIES OF ANISUS VORTICULUS (TROSCHEL 1834) (GASTROPODA: PLANORBIDAE) IN NORTHEAST GERMANY MICHAEL L. ZETTLER Leibniz Institute for Baltic Sea Research Warnemünde, Seestr. 15, D-18119 Rostock, Germany Abstract During the EU Habitats Directive monitoring between 2008 and 2010 the ecological requirements of the gastropod species Anisus vorticulus (Troschel 1834) were investigated in 24 different waterbodies of northeast Germany. 117 sampling units were analyzed quantitatively. 45 of these units contained living individuals of the target species in abundances between 4 and 616 individuals m-2. More than 25.300 living individuals of accompanying freshwater mollusc species and about 9.400 empty shells were counted and determined to the species level. Altogether 47 species were identified. The benefit of enhanced knowledge on the ecological requirements was gained due to the wide range and high number of sampled habitats with both obviously convenient and inconvenient living conditions for A. vorticulus. In northeast Germany the amphibian zones of sheltered mesotrophic lake shores, swampy (lime) fens and peat holes which are sun exposed and have populations of any Chara species belong to the optimal, continuously and densely colonized biotopes. The cluster analysis emphasized that A. vorticulus was associated with a typical species composition, which can be named as “Anisus-vorticulus-community”. In compliance with that both the frequency of combined occurrence of species and their similarity in relative abundance are important. The following species belong to the “Anisus-vorticulus-community” in northeast Germany: Pisidium obtusale, Pisidium milium, Pisidium pseudosphaerium, Bithynia leachii, Stagnicola palustris, Valvata cristata, Bathyomphalus contortus, Bithynia tentaculata, Anisus vortex, Hippeutis complanatus, Gyraulus crista, Physa fontinalis, Segmentina nitida and Anisus vorticulus. -
A Manual for the Survey and Evaluation of the Aquatic Plant and Invertebrate Assemblages of Grazing Marsh Ditch Systems
A manual for the survey and evaluation of the aquatic plant and invertebrate assemblages of grazing marsh ditch systems Version 6 Margaret Palmer Martin Drake Nick Stewart May 2013 Contents Page Summary 3 1. Introduction 4 2. A standard method for the field survey of ditch flora 5 2.1 Field survey procedure 5 2.2 Access and licenses 6 2.3 Guidance for completing the recording form 6 Field recording form for ditch vegetation survey 10 3. A standard method for the field survey of aquatic macro- invertebrates in ditches 12 3.1 Number of ditches to be surveyed 12 3.2 Timing of survey 12 3.3 Access and licences 12 3.4 Equipment 13 3.5 Sampling procedure 13 3.6 Taxonomic groups to be recorded 15 3.7 Recording in the field 17 3.8 Laboratory procedure 17 Field recording form for ditch invertebrate survey 18 4. A system for the evaluation and ranking of the aquatic plant and macro-invertebrate assemblages of grazing marsh ditches 19 4.1 Background 19 4.2 Species check lists 19 4.3 Salinity tolerance 20 4.4 Species conservation status categories 21 4.5 The scoring system 23 4.6 Applying the scoring system 26 4.7 Testing the scoring system 28 4.8 Conclusion 30 Table 1 Check list and scoring system for target native aquatic plants of ditches in England and Wales 31 Table 2 Check list and scoring system for target native aquatic invertebrates of grazing marsh ditches in England and Wales 40 Table 3 Some common plants of ditch banks that indicate salinity 50 Table 4 Aquatic vascular plants used as indicators of good habitat quality 51 Table 5a Introduced aquatic vascular plants 53 Table 5a Introduced aquatic invertebrates 54 Figure 1 Map of Environment Agency regions 55 5. -
Buglife Ditches Report Vol1
The ecological status of ditch systems An investigation into the current status of the aquatic invertebrate and plant communities of grazing marsh ditch systems in England and Wales Technical Report Volume 1 Summary of methods and major findings C.M. Drake N.F Stewart M.A. Palmer V.L. Kindemba September 2010 Buglife – The Invertebrate Conservation Trust 1 Little whirlpool ram’s-horn snail ( Anisus vorticulus ) © Roger Key This report should be cited as: Drake, C.M, Stewart, N.F., Palmer, M.A. & Kindemba, V. L. (2010) The ecological status of ditch systems: an investigation into the current status of the aquatic invertebrate and plant communities of grazing marsh ditch systems in England and Wales. Technical Report. Buglife – The Invertebrate Conservation Trust, Peterborough. ISBN: 1-904878-98-8 2 Contents Volume 1 Acknowledgements 5 Executive summary 6 1 Introduction 8 1.1 The national context 8 1.2 Previous relevant studies 8 1.3 The core project 9 1.4 Companion projects 10 2 Overview of methods 12 2.1 Site selection 12 2.2 Survey coverage 14 2.3 Field survey methods 17 2.4 Data storage 17 2.5 Classification and evaluation techniques 19 2.6 Repeat sampling of ditches in Somerset 19 2.7 Investigation of change over time 20 3 Botanical classification of ditches 21 3.1 Methods 21 3.2 Results 22 3.3 Explanatory environmental variables and vegetation characteristics 26 3.4 Comparison with previous ditch vegetation classifications 30 3.5 Affinities with the National Vegetation Classification 32 Botanical classification of ditches: key points -
European Red List of Non-Marine Molluscs Annabelle Cuttelod, Mary Seddon and Eike Neubert
European Red List of Non-marine Molluscs Annabelle Cuttelod, Mary Seddon and Eike Neubert European Red List of Non-marine Molluscs Annabelle Cuttelod, Mary Seddon and Eike Neubert IUCN Global Species Programme IUCN Regional Office for Europe IUCN Species Survival Commission Published by the European Commission. This publication has been prepared by IUCN (International Union for Conservation of Nature) and the Natural History of Bern, Switzerland. The designation of geographical entities in this book, and the presentation of the material, do not imply the expression of any opinion whatsoever on the part of IUCN, the Natural History Museum of Bern or the European Union concerning the legal status of any country, territory, or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The views expressed in this publication do not necessarily reflect those of IUCN, the Natural History Museum of Bern or the European Commission. Citation: Cuttelod, A., Seddon, M. and Neubert, E. 2011. European Red List of Non-marine Molluscs. Luxembourg: Publications Office of the European Union. Design & Layout by: Tasamim Design - www.tasamim.net Printed by: The Colchester Print Group, United Kingdom Picture credits on cover page: The rare “Hélice catalorzu” Tacheocampylaea acropachia acropachia is endemic to the southern half of Corsica and is considered as Endangered. Its populations are very scattered and poor in individuals. This picture was taken in the Forêt de Muracciole in Central Corsica, an occurrence which was known since the end of the 19th century, but was completely destroyed by a heavy man-made forest fire in 2000. -
Gastropoda: Pulmonata: Planorbidae) in the Laboratory
Vol. 16(4): 207–215 LIFE CYCLE OF ANISUS VORTICULUS (TROSCHEL, 1834) (GASTROPODA: PULMONATA: PLANORBIDAE) IN THE LABORATORY STANIS£AW MYZYK S¹polno 14, 77-320 Przechlewo, Poland ABSTRACT: Laboratory culture of 2004–2007 provided the following data on the life cycle of Anisus vorticulus (Troschel). Snails hatched in May–June and kept in pairs usually started reproducing 42–114 days after hatch- ing, at the shell width of 3.0–5.2 mm and 3.75–5.1 whorls. Some of them continued reproduction next spring. Snails hatched in July-August and kept in pairs produced their first cocoons next year. In the year of hatching the snails produced their last cocoons till October, next year – usually till August. During their lifetime snails kept in pairs produced a maximum of 122 cocoons with a total of 511 eggs (per snail), and the number of eggs per cocoon ranged from 0 to 9. Snails kept in isolation produced a maximum of 10 cocoons (most without eggs, the remaining ones with eggs devoid of oocytes). The life span was 68–776 days (mean 423). KEY WORDS: Gastropoda, Planorbidae, Anisus, life cycle, reproduction INTRODUCTION Shells of Anisus vorticulus (Troschel, 1834) are a small lake, and in the same site in 2004 – a live adult planispiral, with a blunt keel usually situated roughly on a floating leaf of Typha latifolia. at half height of the body whorl. Some shells bear a The first information on the biology of the species delicate conchiolin ridge of variable width along the was provided by PIECHOCKI (1975, 1979). -