Refine
Document Type
- Article (4)
Has Fulltext
- yes (4)
Is part of the Bibliography
- no (4)
Keywords
- Germany (2)
- DNA preservation (1)
- GBOL (German Barcode of Life) (1)
- acetic acid (1)
- capture efficiency (1)
- diversity (1)
- false scorpions (1)
- faunistics (1)
- grazing management (1)
- habitat classification (1)
- inland dunes (1)
- methods (1)
- new record (1)
- pitfall traps (1)
- subalpine habitats (1)
Institute
- Extern (1)
Epigeic spiders were sampled using pitfall traps during one year in an anthropogenic open site within the city of Karlsruhe (Alter Flugplatz Karlsruhe). The area, historically used as a military parade ground and airport, is protected as a Special Area of Conservation (SAC) within the Natura 2000 network of the EU and since 2010 as a German nature reserve. We were interested in the diversity, assemblage structure and distribution of spider species within the area and investigated three different plant formations: sparse grass-dominated vegetation with frequent open sand patches (sandy turf ), closed grassland dominated by the mat-grass (Nardus stricta) and ruderal vegetation with blackberry bushes. 123 species were identified from these captures, including many specialists of xerothermic habitats and rare and endangered species like Alopecosa striatipes, Agroeca lusatica, Haplodrassus dalmatensis, Styloctetor romanus, Typhochrestus simoni and Xysticus striatipes as well as extremely rare species of unclassified red list status like Mysmenella jobi, Theonoe minutissima and Zora parallela. The three investigated habitat types were quite similar concerning α-diversity, while measures of β-diversity indicated a strong species turnover. By performing an ecological habitat analysis (using autecological data on spiders) essential differences between the three habitat types could not be discovered, especially not between mat-grass and sandy turf. However, analysing the guild structures showed that different ways of using habitat resources dominated in the different habitat types. For Nardus-grassland several species could be identified as indicator species. While many xero- and photophiles live in the open grassland, the stenotopic psammophiles of inland dunes in the region were not found. The ruderal area houses a mix of grassland- and forest species.
The usefulness of propylene glycol as capture preservative in pitfall traps, with the aim of using the captured spiders for DNA barcoding, was tested. For this purpose a laboratory experiment on the conserving and/or denaturing effect of propylene glycol on mitochondrial DNA (COI) was set up. For the experiment 110 specimens of the common and abundant wolf spider species Pardosa lugubris were manually captured, killed and incubated from one to four weeks in either pure or watered propylene glycol or 70 % denatured ethanol. Rates of successful sequencing, following a standard protocol, did not differ between samples incubated in propylene glycol and in the more commonly used ethanol. Thus, within four weeks, propylene glycol did not significantly denaturize mitochondrial DNA. In two field studies, pitfall traps with propylene glycol captured more spiders than traps with acetic acid. The effect was significant only in one of two field trials, but then consistent at three different sites and the three dominant spider families. Based on these results and our operating experience, we recommend propylene glycol as a capture preservative for (pitfall) traps to obtain specimens for DNA barcoding identification.
In the course of a long term survey on the effects of grazing on the diversity of alpine grasslands, the false scorpion Chthonius (Ephippiochthonius) poeninus Mahnert, 1979 was recorded for the first time outside of Switzerland. The preferred habitat at the locality Alpe Einödsberg (Germany, Bavaria) differs strongly from previous findings. Our data suggest an association with Nardus grasslands (Geo montani-Nardetum), whereas earlier records originated from leaf litter, moss and mouldy trunks. Furthermore, the new records between 1540 m and 1973 m above sea level are the first from the subalpine region of the Alps (hitherto C. poeninus was known from 550 m to 1450 m). In the study region, extensive grazing seems to have a positive effect on the abundance of the species, while it is missing from intensively grazed pastures.