Higher-level phylogeny of Caelifera (Orthoptera) based on mitochondrial genome data

Mitochondrial genome data have been shown to be effective in resolving deep evolutionary relationships over broad time scale in insects. To date, a total of 19 complete mitochondrial genomes of Orthoptera are available in GenBank, of which nine belong to Caelifera. These nine genomes in turn belong to only two families in Caelifera, Acrididae (8 genomes) and Pyrgomorphidae (1 genome), only a small fraction of the diversity in the suborder which contains about 27 families. In this study, we present nine additional genomes that belong to nine caeliferan families which have not been previously sequenced. Based on these new data and the available data from GenBank, we reconstruct a phylogenetic hypothesis of Caelifera and resolve the relationships among the superfamilies Tridactyloidea, Acridoidea, Eumastacoidea, Pneumoroidea, Pyrgormorphoidea, and Trigonopterygoidea. We also discuss the evolution of tRNA rearrangement in light of the phylogeny.