fungi; herbivorous insects; Lepidoptera; diversity; microbiome; mycobiota

Insect-microbiota-plant interactions have received significant attention recently. Especially an impact of microbiome on trophic relationships can be considered as a hot topic of ecology but also for the application of the knowledge in biological control of pests. Despite the larvae of Lepidoptera (caterpillars) belong to the most important herbivores including also many serious pest species, their microbiota is relatively little known and vast majority of studies is devoted to bacteria. Caterpillar microbiota has been so far regarded as species poor and possibly relictual. Contrary to these conclusions we revealed in preliminary study, that mycobiota could be of importance due to high MOTU richness and incongruence in composition between caterpillar gut and host plant phylloplane. Here we bring first analysis of caterpillarmycobiota-plant tritrophic interactions based on extensive dataset from designed elaborative field sampling. We aimed to determine 2.1 | ANIMAL – FUNGI INTERACTIONS 287 the effect of spatial (from micro-to macro-scale) and temporal variability, host plants (trees) and catterpillars feeding strategy. Using DNA metabarcoding (ITS2 on Illumina MiSeq) we obtained mycobiomes from more than 1500 caterpillars and 500 samples of phyllospheres. Our data confirm our expectation that species diversity and structure of microbiomes are influenced by complex of environmental factors including large number interspecific interactions which should be of focus of subsequent experiments.