Phylogenetic relationships among insect orders based on three nuclear protein-coding gene sequences

► Interordinal phylogeny of insects is investigated using nuclear genes DPD1, RPB1 and RPB2. ► The monophyly of Palaeoptera, Neoptera, Polyneoptera, and Holometabola is supported. ► The interordinal relationships within Holometabola are well resolved. ► Hymenoptera is the sister lineage to all other holometabolous insects. ► Strepsiptera is closely related to Coleoptera, but not to Diptera.