The Evolutionary Study Of The Phyllocoptinae Mites Based On Mitochondrial Genomes(Acari:Eriophyoidea)

Eriophyoid mites(superfamily Eriophyoidea)comprise>4400 species worldwide,which is one of the most species-rich superfamilies of Acari.Eriophyoid mites have small body size(average 200 ?m),vermiform or fusiform body shape and can be distinguished from other mites by two pairs of legs.Eriophyoid mites is a kind of phytophagous mites with high host-plant specificity.In the current classification system,Eriophyoidea is placed in the Arachnida,Acari,Acariformes,Trombidiformes.This taxonomic status was established according to some morphological characteristics,but its morphological plesiomorphies and shared apomorphies were always lack of support of phylogenetic analysis.Because the monophyly of Trombidiformes was rejected in phylogenetic analysis reconstructed by various molecular markers,there are some arguments about the systematic status of high-level taxonomic categories of Eriophyoidea that it does not belong to Trombidiformes.With the development of experiment and sequencing technology,more and more molecular markers have been used in phylogenetic research.Mitochondrial genome has been widely used in phylogenetic analysis of various groups because of its small molecular weight,multiple copies and genetic information different from nuclear genes.Previously,our team have sequenced and annotated five mitochondrial genomes of eriophyoid mites for the first time,and found that the mitochondrial genomes of eriophyoid mites have a very interesting rearrangement phenomenon compared with the ancestral arrangement pattern of the mitochondrial genomes of arthropods.We found that Eriophyoidea is not in Trombidiformes in the analysis of phylogenetic tree constructed by mitochondrial genome to infer the taxonomic position in Acariformes of Eriophyoidea.Although there are few eriophyoid mite samples in this study.it lays a foundation for the study of phylogeny and evolution of eriophyoid mites.On the basis of previous studies.this study focuses on the mitochondrial genome of ten eriophyoid mites which are from Phyllocoptinae(Eriophyidae).Those ten species arePhyllocoptes gaotainensus,Calepitrimerus anomalus,Paraepitrimerus stellarus,Grandiscapitis camelliae,Prominens photiniae,Dipentamerus litseae,Fujianacarus wisterianis,Tegolophus ulmi,Neoepitrimerus platyclad,Phyllocoptrata platyclada.The mitochondrial genomes of all the ten eriophyoid mites are composed of 37 genes.Compared with the ancestors of arthropods,the mitochondrial genomes of the ten species have been rearranged in different degrees.Respectively,the arrangement patterns of mitochondrial genomes of Neoepitrimerus platyclad and Phyllocoptes gaotainensus are the same as those of Epitrimerus sabinae and Rhinotelgum shaoguanense.All ten species have truncated tRNA,and are high degree in the Acariformes.In those ten eriophyoid mites,we found five new species(Phyllocoptes gaotainensus,Calepitrimerus anomalus,Paraepitrimerus stellarus,Grandiscapitis camelliae,Prominens photiniae),and redescribed the genus Dipentamerus.In this study,the mitochondrial genome sequence of 39 mites belonging to the Acariformes,including 14 species of eriophyoid mites,was used in phylogenetic analysis.It was found that the monophyly of eriophyoid mites was supported and clustered with sarcoptiform mites,but it was far from other groups of trombidiform Mites.This result further proves that Eriophyoidea does not belong to Trombidiformes,which provides a strong data support to determine the phylogenetic status of Eriophyoidea in high-level taxonomic categories.This study greatly enriched the mitochondrial genome data of eriophyoid mites to provide more powerful support for our previous research results,and further clarify the taxonomic position of Eriophyoidea in Acariformes.