Complete Mitochondrial Genomes Of Two Genera Of Volucellini With Their Phylogeny

The tribe Volucellini belongs to the subfamily Eristalinae,with 4 genera in the world and only 2 genera in China: The genus Volucella Geoffroy,1762 and Graptomyza Wiedemann,1820.Volucella is mainly distributed in the Palaearctic and Oriental,with a few species in the New North and Australia,but there are no records in the neotropics and Africa.About 51 species have been recorded in the world,and about 23 species in China.Graptomyza Wiedemann,1820 belongs to tropical and subtropical insects,mainly distributed in Southeast Asia,South Asia,East Asia,Africa,Australia and the Pacific region,about 83 species recorded in the world,about 19 species recorded in China.Mitochondrial genome has been widely used in the study of animal origin,evolution and classification,phylogeny and kinship because of its characteristics of maternal inheritance,small molecular,rare gene recombination,faster evolution rate and conserved genes.As of January 2022,it was published with only one complete mitogenome sequence of Volucellini by NCBI database.In this paper,16 new mitogenome sequences of hoverfly were sequenced,and combined with the published sequences of hoverfly in NCBI database,the Maximum Likelihood(ML)phylogenetic trees and Bayesian(BI)phylogenetic trees were constructed,basing on four datasets,which using ML method and BI method respectively.It was compared and analyzed that the basic structural characteristics of mitochondrial genome and phylogenetic relationship between Volucellini and Syrphidae.The main results are as follows:1.Completing mitochondrial genome(mitogenome)of 14 species in tribe Volucellini and2 incomplete control regions of tribe Volucellini were obtained.2.Completing mitogenomes of Volucellini are small circular DNA molecule with a size ranging from 15 Kb to 18 Kb.It contains 37 typical genes,including 13 protein coding genes(PCGs),22 transport RNA genes(t RNA)and 2 ribosomal RNA(r RNA).3.The experiment obtained 16 mitogenome of Syrphidae species,combined a published complete sequence from NCBI.Comparative analysis was conducted based on 17 data.It was found that:(1)In this study,all 16 species of mitogenomes of Volucellini were found to form closed circular double-stranded DNA molecules,and all contained 13 protein-coding genes,22 t RNA genes,2 r RNA genes and non-coding regions.(2)The mitogenome length of the tribe Volucellini is measure to be between 15,621 bp and 16,575 bp.17 species have high A+T content,and the A+T content range from 78.3% to81.4%.(3)It is the same as the model species that the gene sequencing of the tribe Volucellini,and there are not found gene rearrangement.(4)The starting codon of 13 protein-coding genes is ATN and TTG,and the starting codon of nad2 and cox1 genes is ATT.The starting codon of cox3,nad4 and nad4 L genes is ATG.Most stop codons are TAA,and a few genes use TAG and incomplete T as stop codons.(5)The secondary structures of 22 t RNA genes are typical of cloverleaf structure,except for t RNA-Ser1,which lacked one ring.The 16 S r RNA secondary structure has six domains(I,II,III,IV,V and VI,with region III missing).The secondary structure of 12 S r RNA has three domains(I,II and III).3.It were based on 74 mitochondrial genome sequences of Syrphidae and 3 outgroups that Maximum likelihood(ML)and Bayesian(BI)phylogenetic relationships was built.Among the eight phylogenetic topologies,Syrphinae is a monophy group,while Eristalinae did not restore the monophyletic group in most of the developmental trees,and only the ML phylogenetic tree constructed from the PCG12 dataset restored the monophy group.The monophyletic nature of the aphiridae family is well supported,with the genus Volucella and the genus Graptomyza both being monophy.In this study,the phylogenetic relationship between the two genera of Volucellini was well resolved,and the results supported the monophy of Volucellini.The phylogenetic relationship between the two genera is as follows:((((Volucella liupanshanensis + V.nitobei)+ V.bivitta)+(V.latifasciata + V.pellucens))+((V.rufimargina + V.plumatoides)+ V.nigricans))+(((Graptomyza sp1.+ G.sp2.)+(G.complete + G.brevirostris))+((G.flavonotata + G.obtuse)+ G.longqishanica))).