Molecular identification of adult and juvenile linyphiid and theridiid spiders in Alpine glacier foreland communities.

Lorna Raso,Alexander Rief,Michael Traugott,Rüdiger Kaufmann,Daniela Sint

doi:10.1371/journal.pone.0101755

Abstract

In glacier forelands spiders constitute a large proportion of the invertebrate community. Therefore, it is important to be able to determine the species that can be found in these areas. Linyphiid and theridiid spider identification is currently not possible in juvenile specimens using traditional morphological based methods, however, a large proportion of the population in these areas are usually juveniles. Molecular methods permit identification of species at different life stages, making juvenile identification possible. In this study we tested a molecular tool to identify the 10 most common species of Linyphiidae and Theridiidae found in three glacier foreland communities of the Austrian Alps. Two multiplex PCR systems were developed and over 90% of the 753 field-collected spiders were identified successfully. The species targeted were found to be common in all three valleys during the summer of 2010. A comparison between the molecular and morphological data showed that although there was a slight difference in the results, the overall outcome was the same independently of the identification method used. We believe the quick and reliable identification of the spiders via the multiplex PCR assays developed here will aid the study of these families in Alpine habitats.

Highlights

Linyphiidae is the largest spider family in northern Europe with over 400 described species [1]
The molecular multiplex PCR identification system proved to be a good way of identifying linyphiid and theridiid spiders
82% worked with the general primers, demonstrating that there was amplifiable DNA in the samples

Summary

Introduction

Linyphiidae is the largest spider family in northern Europe with over 400 described species [1] These spiders are widely distributed but are more diverse in colder regions [2], where they can be found wandering on snow at below-zero temperatures [3]. It is not surprising that it is a significant group in glacier foreland communities They are present in all areas, even close to the glacier, and may play an important ecological role, bringing nutrients into the system [4]. Their diversity means that considerable effort is required to determine the community composition. Another species-rich family of spiders regularly occurring in northern and alpine habitats are the Theridiidae which includes many species which build three-dimensional webs similar to the ones created by linyphiid spiders and which they resemble in other traits such as body size and structure [5,6,7]

Methods

Results

Conclusion