Fig. 1

Phylogenetic relationships of ionotropic receptors in Lepidoptera and Diptera. Black dots indicate >80 % bootstrap support, grey dots indicated 60–79 % bootstrap support. Shaded colors represent taxon-specific IR genes: Diptera-specific (green lines), IR20a clade (green shade), Lepidoptera-specific (yellow), butterfly-specific (orange), and Heliconius-specific (red). While a large number of genes are conserved between Lepidoptera and Diptera, instances of lepidopteran-, butterfly- and Heliconius-specific IRs emerged from our analysis