Ceropegia species (Apocynaceae) have deceptive pitfall flowers and exploit small flies as pollinators, supposedly by chemical mimicry. Only preliminary data on the composition of flower scents are available for a single species so far, and the mimicry system is not yet understood in any species. We collected data on basic pollination aspects of C. dolichophylla, analyzed floral scent by gas chromatography linked to mass spectrometry, identified electrophysiologically active scent components by gas chromatography coupled with electroantennographic detection, and determined compounds responsible for pollinator attraction in bioassays. We found that flowers of C. dolichophylla are visited by small flies of several taxa. Only Milichiidae and Chloropidae carried pollinaria and are, thus, pollinators. The pollen transfer efficiency at two different sites was 2 % and 4 %, respectively. The floral scent was dominated by spiroacetals, mainly (2S,6R,8S)-8-methyl-2-propyl-1,7-dioxaspiro[5.5]undecane, n-tridecane, and N-(3-methylbutyl)acetamide. This spiroacetal and the acetamide elicited the most intense electrophysiological responses in fly antennae, and bioassays confirmed the capability of the spiroacetal in eliciting behavioral responses in pollinators. Most flies, determined as pollinators of C. dolichophylla, are kleptoparasites. They exploit insect prey of predatory arthropods as food source to which they are attracted by volatiles. 8-Methyl-2-propyl-1,7-dioxaspiro[5.5]undecane and N-(3-methylbutyl)acetamide have not been identified before as volatiles of other plants, however, they are known as insect volatiles. Both compounds occur in the venom glands of paper wasps, a potential food source for the pollinators of C. dolichophylla. We propose that C. dolichophylla shows a kleptomyiophilous pollination strategy. It mimics insect related odors to exploit the food-seeking behavior of its kleptoparasitic pollinators.

The herbal medicinal genus Aconitum L., belonging to the Ranunculaceae family, represents the earliest diverging lineage within the eudicots. It currently comprises of two subgenera, A. subgenus Lycoctonum and A. subg. Aconitum. The complete chloroplast (cp) genome sequences were characterized in three species: A. angustius, A. finetianum, and A. sinomontanum in subg. Lycoctonum and compared to other Aconitum species to clarify their phylogenetic relationship and provide molecular information for utilization of Aconitum species particularly in Eastern Asia. The length of the chloroplast genome sequences were 156,109 bp in A. angustius, 155,625 bp in A. finetianum and 157,215 bp in A. sinomontanum, with each species possessing 126 genes with 84 protein coding genes (PCGs). While genomic rearrangements were absent, structural variation was detected in the LSC/IR/SSC boundaries. Five pseudogenes were identified, among which Ψrps19 and Ψycf1 were in the LSC/IR/SSC boundaries, Ψrps16 and ΨinfA in the LSC region, and Ψycf15 in the IRb region. The nucleotide variability (Pi) of Aconitum was estimated to be 0.00549, with comparably higher variations in the LSC and SSC than the IR regions. Eight intergenic regions were revealed to be highly variable and a total of 58–62 simple sequence repeats (SSRs) were detected in all three species. More than 80% of SSRs were present in the LSC region. Altogether, 64.41% and 46.81% of SSRs are mononucleotides in subg. Lycoctonum and subg. Aconitum, respectively, while a higher percentage of di-, tri-, tetra-, and penta- SSRs were present in subg. Aconitum. Most species of subg. Aconitum in Eastern Asia were first used for phylogenetic analyses. The availability of the complete cp genome sequences of these species in subg. Lycoctonum will benefit future phylogenetic analyses and aid in germplasm utilization in Aconitum species.