Characterization of the complete mitochondrial genome sequence of Asiadodis yunnanensis (Mantidae: Choeradodinae) and phylogenetic analysis.

The complete mitochondrial genome of the praying mantises Asiadodis yunnanensis was characterized in this study. The circular molecule is 15,416 bp in length (GenBank accession no. MN037794), containing 13 protein-coding genes (PCGs), two ribosomal RNA (rRNA) genes, 22 transfer RNA (tRNA) genes. The nucleotide composition is asymmetric (39.5% A, 15.1% C, 9.6% G, 35.8% T), with an overall A + T content of 75.3%. The gene arrangement of A. yunnanensis is identical to that observed in other praying mantises. Seven PCGs are initiated with typical ATN start codons, Four genes (cox1, nad3, nad4L, and nad6) begin with TTN, nad1 begin with GTT, and nad5 use CTT, as initiation codon. Twelve PCGs stop with complete termination codon TAA and TAG, whereas nad5 uses incomplete termination codon (T--). Twenty reading frame overlaps and seven intergenic regions are found in the mitogenome of A. yunnanensis. The phylogenetic relationships based on 13 PCGs show that A. yunnanensis clusters closest to the species of Mantidae.

Asiadodis was established by Roy (2004) to distinguish from Choeradodis. Asiadodis have only been found in Southeast Asia and South Asia. There are two species involved in: A. yunnanensis and A. squilla. A. yunnanensis (Wang and Liang 1995) is a type of praying mantises belonging to the order Mantodea, family Mantidae, subfamily Choeradodinae, genus Asiadodis, distributing in China, Yunnan. Asiadodis yunnanensis captures insect pests as food and is recognized as an important natural enemy for biological control. In this study, samples of A. yunnanensis were collected from China, Mengla, Xishuangbanna, Yunnan (21.47°N, 101.54°E) and stored in the praying mantises specimen room of College of Plant Medicine, Qingdao Agricultural University with an accession number 01-XXBNJH.

The complete mitogenome of A. yunnanensis is a circular molecule of 15,416 bp in length (GenBank under accession no. MN037794) and contains 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), two ribosomal RNA genes (rrnL and rrnS). The nucleotide composition of A. yunnanensis mitogenome is asymmetric (39.5% A, 15.1% C, 9.6% G, 35.8% T), with an overall A + T content of 75.3%. The AT-skew and GC-skew of this genome were 0.049 and −0.223, respectively. The gene organization of A. yunnanensis is similar to that observed in other praying mantises (Ye et al. 2016; Zhang et al. 2018). Twenty-one genes were encoded on the major strand (J-strand), whereas the others were encoded on the minor strand (N-strand).

The A. yunnanensis mitogenome harbours a total of 32 bp intergenic spacer sequences, which is made up of 5 regions in the range from 5 to 10 bp. Gene overlaps were found at nine gene junctions and involved a total of 223 bp, the longest 39 bp overlapping located between nad3 and trnL2. The A + T content of the A. yunnanensis mitogenome was 75.3%. The higher A + T content of A. yunnanensis was present in all regions, both genes and noncoding regions. Gln (Q), Glu (E), and Trp (W) are most frequently used. Moreover, the A + T content were also reflected further in the codon usage: the relative synonymous codon usages showed that A. yunnanensis used more NNA and NNT codon. The rrnL was 1313 bp in length with A + T content of 79.3%, and rrnS was 767 bp in length with A + T content of 74.9%.

Seven PCGs in A. yunnanensis mitogenome start with a typical ATN (ATA and ATG) codon, four genes begin with TTN (TTG, ATC, and TTA), nad1 uses GTT and nad5 use CTT as initiation codon. Twelve PCGs stop with complete termination codon (TAA and TAG), whereas nad5 uses incomplete codon (T––) as termination codon. Based on the Maximum-likelihood analyses, we constructed the phylogenetic relationships of A. yunnanensis and 23 other praying mantises based on the 13 PCGs amino acids using RAxML. Cryptocercus kyebangensis was used as an outgroup. The results have shown that A. yunnanensis is closely clustered with other species in family Mantidae (Figure 1), which agree with the morphology classifications.

Figure 1.

Phylogenetic tree showing the relationship between A. yunnanensis (MN037794) and 23 other praying mantises. Cryptocercus kyebangensis (KP872847.1) was used as an outgroup. The black circle indicates popularity >90. GenBank accession numbers used in the study are the following: Rhombodera valida (KX611804.1), Hierodula formosana (KR703238.1), Tamolanica tamolana (DQ241797.1), Sphodromantis lineola (KY689123.1), Tenodera sinensis (KY689132.1), Hierodulella sp. (KY689136.1), Deroplatys desiccata ( KY689113.1), Mantis religiosa (KU201317.1), Sceptuchus simplex (KY689133.1), Tropidomantis tenera (KY689127.1), Eomantis yunnanensis (KY689138.1), Theopompa sp. (KU201314.1), Humbertiella nada (KU201315.1), Anaxarcha zhengi (KU201320.1), Odontomantis sp. (KY689121.1), Creobroter gemmatus (KU201319.1), Creobroter jiangxiensis (KY689134.1), Parablepharis kuhlii asiatica (KY689117.1), Hestiasula sp. (KY689115.1), Phyllothelys sp.1 (KY689119.1), Phyllothelys sp.(KY689129.1), Toxodera hauseri (KX434837.1), and Paratoxodera polyacantha (MG049920.1). Mantis determined in this study was underlined.