Fauna Europaea: Hymenoptera - Symphyta & Ichneumonoidea.

Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant European terrestrial and freshwater animals, their geographical distribution at the level of countries and major islands (west of the Urals and excluding the Caucasus region), and some additional information. The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing specialists throughout Europe and is a unique (standard) reference suitable for many users in science, government, industry, nature conservation and education. For the Hymenoptera, taxonomic data from one grade (Symphyta) and one Superfamily (Ichneumonoidea), including 15 families and 10,717 species, are included. Ichneumonoidea is the largest superfamily of Hymenoptera and consisting of two extant families, Ichneumonidae and Braconidae. The costal cell of the fore wing is absent, the fore wing has at least two closed cells, the constriction between the mesosoma (thorax + first abdominal segment or propodeum) and the metasoma (remainder of abdomen) is distinct and the parasitoid larvae usually spin a silken cocoon. Also, the metasoma is ventrally partly desclerotized in the vast majority of ichneumonoids.

Spider hosts (Arachnida, Araneae) and wasp parasitoids (Insecta, Hymenoptera, Ichneumonidae, Ephialtini) matched using DNA barcodes.

The study of parasitoids and their hosts suffers from a lack of reliable taxonomic data. We use a combination of morphological characters and DNA sequences to produce taxonomic determinations that can be verified with reference to specimens in an accessible collection and DNA barcode sequences posted to the Barcode of Life database (BOLD). We demonstrate that DNA can be successfully extracted from consumed host spiders and the shed pupal case of a wasp using non-destructive methods. We found Acrodactylaquadrisculpta to be a parasitoid of Tetragnathamontana; Zatypotapercontatoria and Zatypotabohemani both are parasitoids of Neottiurabimaculata. Zatypotaanomala is a parasitoid of an as yet unidentified host in the family Dictynidae, but the host species may be possible to identify in the future as the library of reference sequences on BOLD continues to grow. The study of parasitoids and their hosts traditionally requires specialized knowledge and techniques, and accumulating data is a slow process. DNA barcoding could allow more professional and amateur naturalists to contribute data to this field of study. A publication venue dedicated to aggregating datasets of all sizes online is well suited to this model of distributed science.

Host specificity and temporal and seasonal shifts in host preference of a web-spider parasitoid Zatypota percontatoria.

Current knowledge about polysphinctine parasite wasps' interactions with their spider hosts is very fragmented and incomplete. This study presents the host specificity of Zatypota percontatoria (Müller) (Hymenoptera: Ichneumonidae) and its adaptation to varying host availability. Two years of field observations show that Z. percontatoria is a stenophagous parasitoid that parasitizes only five closely related web-building spiders of the family Theridiidae (Araneae). Within the Theridiidae it attacks only species belonging to a small group of species, here called the "Theridion" group. These hosts have a similar biology, but are available at different levels of abundance and at different sizes over the season. Laboratory experiments showed that this wasp species ignores linyphiid, araneid or dictynid spiders and accepts only theridiid spiders of the "Theridion" group. In the field study, wasp females preferred older juvenile and sub-adult female spider instars with intermediate body size. Only 5% of the parasitized spiders were males. Parasitism in the natural population of theridiid spiders was on average 1.3%. Parasitism was most frequent on two species, Theridion varians Hahn in 2007 and Neottiura bimaculata Linnaeus in 2008. The parasitization rate was positively correlated with spider abundance. The wasp responded adaptively to seasonal changes in host abundance and host body size and shifted host preference according to the availability of suitable hosts during, as well as between, seasons. In spring and summer the highest percentage of parasitism was on T. varians and in autumn it was on N. bimaculata.