02278nas a2200229   4500008004100000245008600041210006900127300001200196490000700208520153000215653002501745653001201770653001601782653002001798653001601818653002101834100001501855700001701870700001901887700001601906856012601922       2011                        eng d00aMolecular detection of trophic links in a complex insect host-parasitoid food web0 aMolecular detection of trophic links in a complex insect hostpar  a786-7940 v113 aPreviously, host-parasitoid links have been unveiled almost exclusively by time-intensive rearing, while molecular methods were used only in simple agricultural host-parasitoid systems in the form of species-specific primers. Here, we present a general method for the molecular detection of these links applied to a complex caterpillar-parasitoid food web from tropical rainforest of Papua New Guinea. We DNA barcoded hosts, parasitoids and their tissue remnants and matched the sequences to our extensive library of local species. We were thus able to match 87% of host sequences and 36% of parasitoid sequences to species and infer subfamily or family in almost all cases. Our analysis affirmed 93 hitherto unknown trophic links between 37 host species from a wide range of Lepidoptera families and 46 parasitoid species from Hymenoptera and Diptera by identifying DNA sequences for both the host and the parasitoid involved in the interaction. Molecular detection proved especially useful in cases where distinguishing host species in caterpillar stage was difficult morphologically, or when the caterpillar died during rearing. We have even detected a case of extreme parasitoid specialization in a pair of Choreutis species that do not differ in caterpillar morphology and ecology. Using the molecular approach outlined here leads to better understanding of parasitoid host specificity, opens new possibilities for rapid surveys of food web structure and allows inference of species associations not already anticipated.10acytochrome oxidase I10adiptera10aHymenoptera10aimmature stages10alepidoptera10aPapua New Guinea1 aHrcek, Jan1 aMiller, S.E.1 aQuicke, D.L.J.1 aSmith, Alex  uhttps://insectafgseag.myspecies.info/en/content/molecular-detection-trophic-links-complex-insect-host-parasitoid-food-web