Refine
Has Fulltext
- yes (4)
Is part of the Bibliography
- no (4)
Keywords
- Biodiversity (1)
- Biogeography (1)
- Cave animal, ecotone (1)
- Ecological modelling (1)
- Ecology (1)
- Population dynamics (1)
- ecological versatility (1)
- mobility (1)
- phylogeography (1)
2012 gab es in Bezug auf die Spinne des Jahres gleich in mehrfacher Hinsicht eine Premiere: eine neue Spinnenfamilie (Tetragnathidae – Streckerspinnen), ein neuer Lebensraum (Höhle) und ein „gemeinsames“ Jahres-Tier (gleichzeitig das Höhlentier des Jahres). Aber alles der Reihe nach, zuerst die Kurzvorstellung der Spinne des Jahres: Meta menardi (Latreille, 1804), die Große Höhlenspinne.
Ein besonders sensibler – und von der Öffentlichkeit kaum wahrgenommener – Lebensraum befindet sich unter der Erdoberfläche. Natürliche Höhlen und künstliche Hohlräume (z.B. Bergwerksstollen) beherbergen eine Vielzahl von Tierarten, die auf für sie lebenswichtige konstante Umweltbedingungen angewiesen sind. Schon kleine Eingriffe des Menschen in diese Ökosysteme können negative Auswirkungen auf die biologische Vielfalt des subterranen Lebensraums haben, die nicht mehr rückgängig zu machen sind. Die Biospeläologie widmet sich der Erforschung des Lebens in Höhlen und der damit verbundenen ökologischen Zusammenhänge. Jedes Jahr werden für die Wissenschaft neue Arten entdeckt, was natürlich auch daran liegt, dass die Erforschung der subterranen Organismen noch an ihrem Anfang steht.
The Culex pipiens complex encompasses five species and subspecies of the genus Culex. Over time, a multitude of morphologically indistinguishable species has been assigned to this complex with several species being classified as important vectors for different diseases. Some species of this complex hibernate in subterranean habitats, and it has been proven that viruses can survive this phase of hibernation. However, studies focusing on the environmental requirements, ecology and spatial and temporal distribution patterns of mosquitos in underground habitats are sparse. Here, we investigate the main environmental factors and dependencies of Culex, considering the number of individuals and survival probabilities in underground habitats during the winter months. Methods. Since the State of Hesse, Germany harbors about 3500 to 4000 subterranean shelters ample availability of subterranean habitats there provides a good opportunity to conduct detailed investigations of the Culex pipiens complex. In this study, we identified a sample of 727 specimens of overwintering females within the Culex pipiens complex from 52 different underground sites collected over a period of 23 years using qPCR. A complete data set of samplings of hibernating mosquitos from 698 subterranean habitats in Central Germany over the same period was available to study the spatial and temporal patterns and the effect of temperature and precipitation conditions on these hibernating populations using a generalized linear model (GLM). Results. Our qPCR-results show, similar to aboveground studies of mosquitos, that Culex pipiens pipiens and Culex torrentium occur sympatrically. On the other hand, Culex pipiens molestus occurred very rarely. The GLM revealed no shifts in species composition over time, but different preferences for subterranean hibernacula, chemical effects on overwintering populations as well as effects of annual and seasonal mean temperature and precipitation during the active phase from March to November. Cx. p. pipiens and Cx. torrentium are the most common species within Hessian caves and other underground habitats during winter. They co-occur with different frequency without any patterns in species composition. Weather conditions influence the number of overwintering mosquitos during the activity phase. Depending on cave parameters, the number of mosquitos decreases during the winter months.
Speolepta leptogaster (Winnertz, 1863) is frequently occurring in European subterranean environments. As for most cave animals, studies addressing non-anatomical aspects are sparse. Here we present the first molecular study on S. leptogaster. We investigated the demographic structure (i.e. COI locus) of 69 specimens from 36 underground populations in Hesse (Central German Uplands) to get first insights into the species’ dispersal ability.
In total, 14 haplotypes were revealed. Haplotype diversity was relatively high, whereas nucleotide diversity was low. Furthermore, a significant but low pattern of isolation-by-distance and (a) past population expansion event(s) were detected.
Our genetic results suggest a (good) active dispersal ability for Speolepta leptogaster. The occurrence of several surface records of adult specimens corroborates this hypothesis. We discuss the developmental stages of S. leptogaster in the context of the ecological classification system and regard the species as a eutroglophile. Evidence has been found to distinguish two larval types. A reconstructed life-cycle of the species is provided.