Die Land- und Süßwassermollusken im Inselsee bei Güstrow und seiner Umgebung (Deutschland: Landkreis Rostock)

Abstract

Im Rahmen des 38. Kartierungstreffens der Arbeitsgruppe Malakologie Mecklenburg-Vorpommern wurde die Land- und Süßwassermolluskenfauna des Inselsees bei Güstrow und seiner Umgebung erfasst. Dadurch konnte ein wichtiger Beitrag zur Molluskenkartierung in unserem Bundesland geleistet werden, denn es wurden in dem in den letzten zwei Jahrzehnten nur sporadisch bearbeiteten Gebiet 103 Molluskenarten nachgewiesen. Die Ergebnisse wurden mit den Daten früherer Erhebungen verglichen. Für den Inselsee konnten mit Ferrissia fragilis, Marstoniopsis scholtzi und Pseudanodonta complanata drei Neunachweise verzeichnet werden, während die Vorkommen von sechs früher nachgewiesenen Arten nicht bestätigt wurden. Somit sind aus diesem See nunmehr insgesamt 51 Arten gemeldet. Der offensichtlich durch Fraßdruck des invasiven ponto-kaspischen Amphipoden Dikerogammarus villosus in den letzten Jahren ausgestorbene Theodoxus fluviatilis wurde nur noch als Leergehäuse gefunden. In Moorseen in der Umgebung des Inselsees gelang unter anderem der Nachweis von Anisus vorticulus, einer Art der Anhänge II und IV der FFH-Richtlinie. Unter den 52 nachgewiesenen Landschneckenarten ist insbesondere der Nachweis rezenter Leergehäuse von Vallonia enniensis erwähnenswert. During the 38th mapping meeting of the working group malacology in Mecklenburg-West Pomerania, the land and fresh water molluscs of Lake Inselsee and vicinity near Güstrow were assessed, to provide a substantial contribution to the knowledge of mollusc mapping in our federal state. In this previously only sporadically studied area, as much as 103 species were recorded. The results were compared with earlier studies. Within Lake Inselsee, three species were found for the first time: Ferrissia fragilis, Marstoniopsis scholtzi and Pseudanodonta complanata. Six of the formerly recorded species were not found again. Altogether 51 species of molluscan fauna are known from the lake. Theodoxus fluviatilis was observed as empty shells only and has probably disappeared within recent years owing to predation by the invasive Ponto–Caspian amphipod Dikerogammarus villosus. In fen lakes near Lake Inselsee we encountered Anisus vorticulus, a species listed in the EU Habitats Directive (annex II and IV). Among the recorded 52 land snail species, the record of fresh shells of Vallonia enniensis is worth mentioning in particular.

Intra-seasonal hydrological processes on the western Tibetan Plateau: Monsoonal and convective rainfall events ∼7.5 ka ago

“…Classification, and biological and ecological traits of early Middle Holocene molluscs from the study area using the best modern analogue approach. Compiled from Burky et al, 1981;Clewing et al, 2013Clewing et al, , 2014aClewing et al, , 2014bFrömming, 1956;Gittenberger et al, 1998;Glöer, 2002;Killeen et al, 2004;Meier-Brook, 1969, 1975Økland and Kuiper, 1982;Økland, 1990;Taft et al, 2012Taft et al, , 2013Turner et al, 1998;Wilckens, 2014;Zettler et al, 2006; and personal observations.…”

The bay barnacle Amphibalanus improvisus (Darwin, 1854) in the Pleistocene of Europe? A review of Pleistocene Balanidae of northern Central Europe

“…Among the deposits assigned to PZ 5 there was a mixture of brackish water fauna with fresh water molluscs such as Theodoxus serratiliniformis , Viviparus diluvianus , Bithynia tentaculata and V. piscinalis . Although some fresh water molluscs such as B. tentaculata and V. piscinalis also show tolerance of low salinities and are also found in estuaries (Glöer, 2002; Zettler et al, 2006), one can nevertheless assume that, during the transgression, re‐deposition and the mixing of fauna also occurred, the latter particularly towards the end of the Holsteinian transgression.…”

Distinct stages of the intestinal bacterial community of Ampullaceana balthica after salinization

“…The high mortality indicated that the freshwater population of A. balthica used for the laboratory experiments has limited capacities to osmoregulate during a sudden salinity increase. However, A. balthica can be found at a salinity of >15 in coastal areas, demonstrating its general capability to adapt to elevated salinity ( Zettler et al, 2006 ). The high levels of energy reserves of the snails taken at salinity 6 on the coastal sites indicated that the long-term adaptation to elevated salinity is not associated with the impaired energy status ( Figure 2 ).…”

“…A. balthica feeds on detritus, periphyton, diatoms, and filamentous algae ( Gordon et al, 2018 ) and can selectively forage for high-quality food particles ( Fink and Von Elert, 2006 ). It is typically found in freshwater but can tolerate salinity up to 15 ( Zettler et al, 2006 ).…”