Species Delimitation Of The Genus Fruhstorferiola (Orthoptera:Acrididae:Melanoplinae) In China Based On Mitochondrial Genome And SNP Data

Fruhstorferiola is a small genus in the Melanoplinae,with 13 known species worldwide.Previous studies have found that the morphological characters used in the past to identify many species within the Fruhstorferiola show significant variation within species and even between individuals within populations,which cannot be used in practice to distinguish between identifying species,thus the validity of the species is questioned.The analysis of whole mitochondrial genome data suggests that there are significant differences between the three species groups,but the boundaries between species within the groups are not clear.In this paper,we further explore the relationships between species of the Fruhstorferiola based on SNP data,test their morphological taxonomic accuracy and elucidate their phylogenetic relationships,building on previous mitochondrial genomic studies in the laboratory,and obtain the following results:1.A sufficient number of high quality SNP loci were obtained.All samples sequenced in this study had a reads fragment length of 250 bp,an average Q30 of 93.7%,a data volume of more than 20 G for each sample,and an average QC content of 42%.2179 GB of data were obtained,with an average sequencing depth of 5.7×.A total of 31,158 high quality SNP loci were obtained for subsequent genetic analysis after filtering out low quality loci and retaining 80%of the loci that were present in all samples.2.From the phylogenetic tree,although species of the F.huangshanensis group differed significantly morphologically from those of the F.viridifemorata group,and the male caudal whiskers were clearly different in shape,they did not form two independent branches that were monophyletic to each other on the phylogenetic tree constructed based on whole mitochondrial genome data.However,a phylogenetic tree based on SNPs data showed different results,with the species of the two species groups consistently divided into two independent branches that are monophyletic to each other,and the F.huangshanensis group branch having a significantly larger branch length.This suggests that the F.huangshanensis group is an independently divergent taxon,consistent with morphological trait differences.3.In this study,although the independent status of the F.huangshanensis group was supported by the SNPs data,the independence and validity of the species within the group were not supported.Neither the whole mitochondrial genome nor the nuclear genome data could distinguish F.cerinitibia from F.sibynecerca.The results of genetic distance analysis,PCA,and population structure analysis based on SNPs data did not support the independence of the three species in the F.huangshanensis group.Therefore,it is highly likely that the three species in the F.huangshanensis group are the same species.4.In the phylogenetic tree based on SNPs data,most of the samples of the geographical populations of each species in F.viridifemorata group were able to form independent branches,and F.kulinga with two populations and F.viridifemorata with six populations did not form independent branches of mutual monophyly by species in all phylogenetic trees.The results of the species definition analysis based on SNPs data indicated that the population of F.kulinga has a rich species diversity,and although there is some genetic differentiation between F.viridifemorata collected from different areas and other species within the species group,it is highly likely that several species within the F.viridifemorata group are also the same species in this study.In summary,the analysis of SNPs from the 86 samples showed that F.huangshanensis group had diverged from the F.viridifemorata group,and there was no incomplete genealogical sorting between the two species groups.Within the F.huangshanensis groups F.cerinitibia and F,sib are synonyms,and the three species in the group may be the same species.At the same time,we also found that the F.viridifemorata population has rich species diversity,and although there is some genetic differentiation between F.viridifemorata and other species in the group collected from different regions,several species in the F.viridifemorata group in this study are most likely to be the same species.