The complete mitochondrial genome of the lychee stinkbug Mattiphus splendidus (Hemiptera: Tessaratomidae).

The lychee stinkbug Mattiphus splendidus is an important pest which mainly distributed in southern China. In this study, we sequenced and described the complete mitochondrial genome (mitogenome) of M. splendidus, which is the first record in the genus Mattiphus. This mitogenome is 15,973 bp long and comprises of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and a control region. Gene order is identical to that of the putative ancestral arrangement of insects. All protein-coding genes initiate with ATN, expect ND1and COI use GTG or TTG as start codons and terminate with TAG or TAA, expect COI and COIII use TA or a single T residue as the stop codon. All tRNAs, ranging from 62 to 74 bp, can be folded into typical clover-leaf structure expect for tRNASer(GCU) and tRNAVal . The control region is 1,357 bp long with 73.5% A + T content. The phylogenetic analysis supports the monophyly of Tessaratomidae and the sister relationship between M. splendidus and Eusthenes cupreus.

The family Tessaratomidae is mainly distributed in Asia and Africa (Rolston et al. 1994; Kment & Vilímová 2010; Carvajal et al. 2018) and comprises 267 species, which classified in 64 genera currently (Magnien and Pluot-Sigwalt 2016; Carvajal et al. 2018). Here, we sequenced and described the complete mitochondrial genome (mitogenome) of Mattiphus splendidus from subfamily Tessaratominae. The samples were collected in Ningming, Guangxi, China (22°04′40.3″N 107°36′0.7″E). Voucher specimen was stored at the Entomological Museum of China Agricultural University (No. HEM-064) and the sequence was deposited in GenBank (Accession number: MN496304).

The complete mitogenome of M. splendidus is 15,973 bp in length with 37 typical insect mitochondrial genes (13 protein-coding genes, 22 transfer RNA genes, and two ribosomal RNA genes) and a control region. Gene order is identical to that of the putative ancestral arrangement of insect (Cameron 2014; Song et al. 2016; Li et al. 2017; Liu et al. 2019). A total of 39 bp overlapped nucleotides are found in 9 locations between neighboring genes, ranging from 1 to 8 bp in length, while totally 65 bp intergenic nucleotides in 14 locations, ranging from 1 to 18 bp in size.

The A + T content of the mitogenome is 72.7% (A = 42.10%, T = 30.6%, C = 15.4%, G = 11.9%), showing obvious bias toward AT with positive AT-skew (0.16) and negative GC-skew (−0.13). Eleven protein-coding genes initiate with ATN as the start codon (six with ATG, three with ATA, and two with ATT). The exceptions are the ND1 gene and the COI gene, which use GTG and TTG as start codons respectively. Conventional stop codons TAG and TAA are respectively distributed to three and eight protein-coding genes. However, COI terminate with TA, and COIII use a single T residue as the stop codon (Song et al. 2019; Zhao et al. 2019).

There are 22 tRNA genes, ranging from 62 to 74 bp in length, and all of them can be folded into typical clover-leaf secondary structure expect for tRNA and tRNA, the dihydrouridine (DHU) arm of which forms a simple loop, as is common phenomenon in most insects (Jiang et al. 2016). The length of lrRNA and srRNA is 1278 bp and 805 bp, respectively. The A + T content of lrRNA and srRNA are determined to be 76.7% and 73.8%. The control region is located between srRNA and tRNA, which is 1357 bp long with 73.5% A + T content.

Phylogenetic tree based on the dataset of the 13 protein-coding genes and two rRNA genes was constructed by the maximum likelihood method (Figure 1). Each family showed a monophyletic cluster. Family Tessaratomidae was genetically closely related to family Dinidoridae, and the sister relationship between M. splendidus and Eusthenes cupreus was highly supported.

Figure 1.

Phylogenetic relationship of Mattiphus splendidus and other 17 Pentatomoidea species which was inferred from ML analysis of the 13 protein-coding genes and two rRNAs genes and generated by IQ-TREE 1.6.5 (Trifinopoulos et al. 2016). Number above each node indicates the ML bootstrap support values. The newly sequenced mitogenome is highlighted by the asterisk.