Comparison of mitochondrial gene arrangement between barklice, booklice and the hypothetical ancestor of insects.

Abbreviations of species names are: Pa for P. albimaculata, Lh for L. hyalospilus, Dy for Drosophila yakuba, Le for lepidopsocid, and Lb for L. bostrychophila. Abbreviations of gene names follow Figure 1. Genes are transcribed from left to right except those underlined, which have the opposite transcriptional orientation. Pa and Lh have the same set of mt genes and gene arrangement, except the control region and the adjacent trnM gene due to our unsuccess to amplify this region in Lh. Shared gene boundaries are indicated by brackets and letter codes: A) trnY-cox1-trnL2; B) from trnK to cox3; C) atp8-atp6; D) trnF-nad5; E) trnS1- trnE; F) from trnH to cytb; G) from nad1 to CR; and H) trnQ-nad2. Two ancestral gene blocks highlighted by the orange; broken lines indicate the inferred blocks that had duplicated in tandem. The circling arrows indicate inversions of mt genes relative to the hypothetical ancestor of insects.