Species Delimitation Of Haplotropis Brunneriana And Its Related Species Based On Geometric Morphology And DNA Barcoding

Haplotropis brunneriana and its related species belong to the Orthoptera,Acridoidea,Pamphagidae,Pamphaginae,Haplotropidini,which are one of the pests of food crops and other cash crops.The morphological characteristics of the Haplotropis brunneriana and its related species are very similar,and the species definition is controversial in the research of domestic and foreign scholars,and the identification characteristics standards cannot be unified.Species were mostly divided based on qualitative analysis of morphological characteristics in traditional taxonomy,which is often difficult to accurately distinguish and identify species with similar morphology.Objective quantitative data statistical analysis was conducted on the external morphological characteristics of the research object by the geometric morphology method,and DNA barcoding which is a new method for biology taxonomy that combined molecular biology and bioinformatics was used to identify species and analyze phylogenetic relationship at the molecular level,which improve the accuracy and efficiency of species identification.In this study,to study the species definition of Haplotropis brunneriana and its related species,geometric morphology and DNA barcoding methods were used,respectively.The two morphological characteristics,the pronotum and forewing,which have important taxonomic status in genus and species identification,were selected to quantitatively compare280 samples from 4 genera and 11 species of the Haplotropis brunneriana and its related species.The morphological differences of lateral and dorsal views of the pronotum and forewing between genera and species were analyzed.Whether the morphological changes of pronotum and forewing can be used as a morphological classification characteristics between genera and species,and the stability and confidence in identification classification of pronotum and forewing in related species were explored.And the DNA barcoding data of 31 samples of 4 genera and 5 species were determined,and the ABGD method and j MOTU method were used to classify the species.The maximum likelihood tree(ML tree)and the Bayesian tree(BI tree)were reconstructed,and the phylogenetic relationship was analyzed.The research results are as follows:1.The part with the greatest morphological change in the lateral view of the pronotum is the angular between median carina and posterior margin,and the part with the largest morphological change in the dorsal view of the pronotum is the angular protrusion of posterior margin.The variation of these two characteristics can distinguish different genera and different species in the canonical variable analysis(CVA),which has reached the level of distinguishing genus and species,indicating that they can be used as genus-level and specieslevel identification features.This is consistent with the traditional taxonomy that the pronotum is used as a genus and species identification feature.2.The length-width ratio of the forewings tends to become larger,and its difference in morphological changes cannot distinguish different genera in the canonical variable analysis,but can distinguish different species,only to the degree of species identification,indicating that it can be used as an identification feature of species level.This is consistent with the traditional taxonomy that forewing is used as an identification feature between species.3.In the geometric morphological analysis based on the lateral view of the pronotum,the dorsal view of the pronotum and forewing,the 15 specimens of the genus Sulcotropis from Chengde all can be distinguished from the Sulcotropis cyanipes and Sulcotropis xiaowutaiensis in the genus Sulcotropis.It is speculated to be a new species and tentatively named Sulcotropis chengdeensis sp.nov.4.The ABGD and j MOTU method based on DNA barcoding divided the ingroup into 7groups.The ML and BI trees reconstructed based on DNA barcoding showed that most of the specimens of the same species clustered into one branch,which was consistent with the view of traditional morphological,geometrical morphological,ABGD and j MOTU methods for species division.The Sulcotropis chengdeensis sp.nov.clustered into a single branch,which supports the speculation that it is a new species.5.The research results based on geometric morphology and DNA barcoding all support the establishment of the genus Haplotropis,Sulcotropis,Humphaplotropis,Sulcohumpacris.