Similarly, the pergid Heteroperreyia hubrichi was initially selected as a candidate for biological control of the Brazilian peppertree, Schinus terebinthifolius, an invader to Florida, California and Hawaii. However, the introduction of that sawfly has been delayed, again because of its potential for poisoning native wildlife and domesticated animals that may consume the insect larvae. In the past, large batches of probably thousands of larvae were required to isolate, identify, 
and quantify the peptides, by using oven or freeze dried larvae. For the current study, we designed an extraction procedure using single larvae, and performed liquid chromatography�Cmass spectrometry analyses. This allowed us for the first time, to include relatively rare target Nodakenin species and to estimate inter-individual variation in peptide profiles. The screening of numerous Pergidae and Argidae species reveals that most of them contain the peptides. In many living organisms, including sawflies, taxonomic affiliation across species is reflected in congruent chemically-based defensive strategies. The fact that previously only four species from two sawfly families were known to contain toxic peptides, was not representative of their actual occurrence in nature but a strong underestimation of the actual number of species containing such peptides. Our study has discovered the presence of toxic peptides in most of the analyzed species of Pergidae and Argidae, two families that are closely related. Since the peptides were not detected in any outgroup species, it is likely that their occurrence is restricted to the two sawfly families. The extraction procedure used here is the first that allows chemical analysis of single specimens, which offers several advantages over earlier methods described in the literature and which are all based on large amounts of oven-dried specimens. Our methodology appears as robust in that the presence or absence of at least one of the peptides was constant across all individuals of a given species. It is unlikely that a contamination of the LC-column has affected the results, since daily blanks were performed, and the samples analyzed in triplicate on different days gave, nevertheless, similar results. The chemical analyses revealed intraspecific variation in peptide concentrations, among individuals as well as populations. The two populations of L. interrupta were sampled on host plants belonging to different genera; they showed similar concentrations of VPerg but different concentrations of Perg. In Australia, L. zonalis has the potential to poison grazing livestock, although no such case has been reported. It remains unclear to what extent geographical and/or other factors may affect the chemical profiles. However, the two populations of A. pagana, sampled in different years and at different locations, had similar chemical profiles, suggesting that there is no temporal and geographical influence on the chemistry of this species. More generally, the biosynthesis of the peptides remains unknown, not the host plant but endosymbionts being supposed to Pancuronium dibromide produce them. Some of our results are strikingly different from those reported in the literature. Intriguingly, differences between the respective two data sources are quantitative but also qualitative. The differences in chemical profiles may have multiple causes and remain difficult to extricate. The methods of extracting and chemically analyzing the compounds may impact the results, and our LC-MS analyses generally seem to slightly overestimate the peptide amounts, as shown by the recovery experiments.