Our treasure of the month: A daddy-long-leg spider
Die Zitterspinne aus dem Bestand des “GBOL III: dark taxa”-Projekts. © Björn Rulik
Who doesn’t know them, the little spiders with the long legs that can be found in many houses? They are particularly prevalent in cellars and hallways: Daddy-long-leg spider or cellar spiders. The best-known species in Germany is Pholcus phalangioides – our treasure of the month.
Here, however, we see a cellar spider specimen that has yet to be examined. It origins from the project “GBOL III: Dark Taxa”. The goal of this project is to increase the knowledge on the German fauna within the two most diverse and understudied groups Diptera and Hymenoptera, that means working on the unknown, small creepy-crawlies about which we still don’t know much in Germany. Including spiders from time to time.
Additionally, we are interested in the parasites, that affect the eggs of cellar spiders. Pholcid spider females carry their egg-sacs with their mouthparts until the spiderlings hatch and it is probably for this reason that the eggs are not densely covered by a protective layer of silk as in most other spider families. Few cases of egg-parasitism were discovered, and in some cases the female spiders were kept alive until the wasps emerged. Several different spider genera are affected, and it seems that at least four different wasp species are involved.
The LIB Museum Koenig Bonn houses the world’s most important collection of these animals. With over 800 species from almost all known genera, it is the most taxonomically comprehensive collection worldwide. It offers the highest species diversity, represented by a total of 380 type specimens and, with over 26,000 adult individuals, is also numerically larger than any other. In addition, the objects are geographically the most balanced in comparison, having been collected on over 40 expeditions, in as many countries in Asia, Europe, Africa and America. Since the material is prepared in pure alcohol or stored frozen, it is also suitable for molecular work.
The collection continues to be constantly expanded and forms an important basis for spider research at the LIB. More than 60 scientific papers of the last 20 years are largely or exclusively based on specimens from the Bonn cellar spider collection.
For further information:
https://bolgermany.de/home/gbol3/projects/
https://bonn.leibniz-lib.de/en/research/projects/egg-parasitism-in-pholcid-spiders
