摘要:SummaryDragonflies and damselflies are among the earliest flying insects with extant representatives. However, unraveling details of their long evolutionary history, such as egg laying (oviposition) strategies, is impeded by unresolved phylogenetic relationships, particularly in damselflies. Here we present a transcriptome-based phylogenetic reconstruction of Odonata, analyzing 2,980 protein-coding genes in 105 species representing nearly all the order’s families. All damselfly and most dragonfly families are recovered as monophyletic. Our data suggest a sister relationship between dragonfly families of Gomphidae and Petaluridae. According to our divergence time estimates, both crown-Zygoptera and -Anisoptera arose during the late Triassic. Egg-laying with a reduced ovipositor apparently evolved in dragonflies during the late Jurassic/early Cretaceous. Lastly, we also test the impact of fossil choice and placement, particularly, of the extinct fossil species, †Triassolestodes asiaticus, and †Proterogomphus renateaeon divergence time estimates. We find placement of †Proterogomphus renateaeto be much more impactful than †Triassolestodes asiaticus.Graphical abstractDisplay OmittedHighlights•Relationships of dragonflies and damselflies are unraveled using transcriptomes•Earliest flying insects – Odonata and extinct relatives – date back to Permian period•Both extant dragonflies and damselflies started diverging in the Triassic periodEvolutionary biology; Phylogenetics