A Novel Mitochondrial Genome Fragmentation Pattern in the Buffalo Louse Haematopinus tuberculatus (Psocodea: Haematopinidae)

Sucking lice are obligate ectoparasites of mammalian hosts, causing serious public health problems and economic losses worldwide. It is well known that sucking lice have fragmented mitochondrial (mt) genomes, but many remain undetermined. To better understand patterns of mt genome fragmentation in the sucking lice, we sequenced the mt genome of the buffalo louse Haematopinus tuberculatus using next-generation sequencing (NGS). The mt genome of H. tuberculatus has ten circular minichromosomes containing a total of 37 genes. Each minichromosome is 2.9–5.0 kb long and carries one to eight genes plus one large non-coding region. The number of mt minichromosomes of H. tuberculatus (ten) is different from those of congeneric species (horse louse H. asini, domestic pig louse H. suis and wild pig louse H. apri) and other sucking lice. Two events (gene translocation and merger of mt minichromosome) are observed in Haematopinus. Compared to other studies, our phylogeny generated from mt genome datasets showed a different topology, suggesting that inclusion of data other than mt genomes would be required to resolve phylogeny of sucking lice. To our knowledge, this is the first report of a ten mt minichromosomes genome in sucking lice, which opens a new outlook into unexplored mt genome fragmentation patterns in sucking lice.