Complete mitochondrial genomes of two cockroaches, Blattella germanica and Periplaneta americana, and the phylogenetic position of termites

Abstract

The mitochondrial genomes are one of the most information-rich markers in phylogenetics. The relationships within superorder Dictyoptera have been debated in the literature. However, the closely related termites (Isoptera) are retained as unranked taxon within the order Blattaria (cockroaches). In this work, we sequenced the complete mitogenomes of two cockroaches, reconstructed the molecular phylogeny and attempted to infer the phylogenetic position of termites in Blattaria more reliably. The complete mtDNA nucleotide sequences of the peridomestic American cockroach (Periplaneta americana L.) and the domestic German cockroach (Blattella germanica L.) are 15,025 and 15,584 bp in size, respectively. The genome shares the gene order and orientation with previously known Blattaria mitogenomes. Most tRNAs could be folded into the typical cloverleaf secondary structure, but the tRNA-Ser (AGN) of P. americana appears to be missing the dihydrouridine arm. Using nucleotide and amino acid sequences as phylogenetic markers, we proposed that termites should be treated as a superfamily (Termitoidea) of cockroaches. We suggested that Polyphagoidea was the sister group of Termitoidea in Blattaria and supported that the suborder Caelifera is more closely related to the Phasmatodea than to the suborder Ensifera of Orthoptera.

The complete mitogenome of the wood-feeding cockroachCryptocercus kyebangensis(Blattodea: Cryptocercidae) and phylogenetic relations among cockroach families

“…To date, complete mitogenome sequences of seven species from four families (Cryptocercidae, Blattidae, Blattellidae, and Polyphagidae) of the order Blattodea have been published (Yamauchi et al 2004;Zhang et al 2010;Cameron et al 2012;Xiao et al 2012;Chen 2013). We show phylogenetic relations among cockroach families based on the amino acid sequences derived from 13 mitochondrial protein-coding genes (PCGs) in the whole mitogenome.…”

<span lang="EN-US"><span style="font-family: 'Times New Roman'; font-size: small;"><strong>Order Blattodea. <em>In</em>: Zhang, Z.-Q. (Ed.) Animal Biodiversity: An Outline of Higher-level Classification and Survey of Taxonomic Richness (Addenda 2013) </strong></span></span>

“…Inward and subsequent phylogenetic studies (Legendre et al 2008;Ware et al 2008;Cameron et al 2012;Djernaes et al 2012;Xiao et al 2012) have confirmed that the termites and the cockroach family Cryptocercidae are sister groups and that this clade is nested within the Blattodea. Since the termites had previously been classified as an order (Isoptera), a lower rank for this group was required.…”

Complete mitochondrial genomes of two blattid cockroaches, Periplaneta australasiae and Neostylopyga rhombifolia, and phylogenetic relationships within the Blattaria

“…The primers were designed from aligned conserved nucleotide sequences of Periplaneta americana [10] and Periplaneta fuliginosa [24]. Then, based on the obtained sequences, species-specific primers were designed using Primer Premier 5.0 to amplify the overlapping fragments.…”

“…Primers Nr1F and Pa1F were from Du et al [25]. Primers Nr9F, Nr9R, Nr10F, and Pa10F were from Xiao et al [10]. Within each PCR product, the full double-stranded sequence was determined by primer walking (PTC-100 thermal cycler, BioRad, Hercules, CA).…”

“…However, some studies showed Isoptera was nested within Blattaria (Blattaria and Isoptera together are called Blattodea) [9–10]. Although there are many studies on the relationships among the dictyopteran subgroups, the consensus about the relationships among different dictyopteran lineages has not been reached.…”