Taxonomy And Phylogeny Of Xyleborini (Coleoptera:Scolytinae) Beetles In Jiangxi Province

The tribe Xyleborini(Coleoptera: Scolytinae),commonly known as wood-boring beetles,also known as ambrosia beetles,which is a kind of potential forest pest with the most economically importance.Many species of the Xyleborini beetles(including non Chinese species)have been classified as quarantine objects or potentially harmful insects,which has became the most aggressive and aggressive group of Scolytid beetles.Therefore,the basic taxonomy and phylogenetic studies of the Xyleborini beetles in Jiangxi Province can lay the foundation for the quarantine identification,prevention and control,and molecular biology researches.At present,the classification of Xyleborini beetles are indistinct,many spices are synonymy or taxonomic changes,and there are still some generic limits are not clearly defined.In this paper,the taxonomy of Xyleborini beetles in Jiangxi area have been studied and supplemented,and the distribution of them in China fauna have been analyzed,at the same time,based on the 28 S r DNA,CAD and COI genes,the molecular identification of Xyleborini beetles in Jiangxi area was performed,and based on the 28 S r DNA,CAD genes,the preliminary phylogenetic analysis of Xyleborini beetles was carried out.The results are as follows:1?Xyleborini beetles from Jaingxi area have been investigated and studied,23 species belonging to 17 genera are identified in the area,among which 14 species are new records to Jiangxi fauna and 3 species are new records to China fauna,one spices is unidentified.Their historical scientific names,synonymy,distribution in China,voucher specimens,hosts and the main external morphology,illustrations of female adult and male adult(If none then not present)of 14 new records spices and the biology of 5 potential hazard species are briefly described.Basic information for plant protection and quarantine is provided.Meantime,we should pay attention to the danger that Xyleborini beetles may bring.2?In the 7 areas of Chinese zoogeographical regions,most of them mainly distribute in the Central region and South region,and a little of them are distribute in Southwest region and Qinghai-Xizang region,some are scatter in North region and Northeast region,and one spices Xyleborinus saxesenii(Ratzeberg)distribute in Mongolia-Xinjiang region,which is the only one spices distribute in all 7 areas of Chinese zoogeographical regions.On the whole,the Xyleborini beetles from Jiangxi area are mainly distributed in the south of China,and are relatively few distributed in the north.There are quite possible to cause damage in the south of China than in the north.3?Comprehensive morphological identification results and molecular identification results of 28 S r DNA,CAD and COI genes,the results show that 16 species of Xyleborini beetles in Jiangxi area have been completely identified,which confirmed the results of morphological identification,indicating the correctness and scientificity of species identification.The genetic distance of 3 marker genes of 28 S r DNA,CAD and COI was analyzed.The nuclear genes of 28 S r DNA,CAD reflected that the interspecific divergence and the intraspecific divergence are minor,while the interspecific divergence and the intraspecific divergence of the mitochondrial COI gene is relatively differ,so it can effectively distinguish Xyleborini beetles by using mitochondrial COI gene.But in the three marker genes,the interspecific divergence and the intraspecific divergence among Xyleborini beetles are overlapped,especially between Anisandrus ursulus and Anisandrus ursinus =(Xylosandrus ursinus),the interspecific divergence between them is in the range of intraspecific divergence of Xyleborini beetles,maybe the classification status of them is still problematical,and it needs further research.4?The phylogenetic relationship between the two marker genes revealed by the integrated nuclear gene 28 S r DNA and the nuclear encoded protein gene CAD was greatly defference.The results of the latest international molecular study of Xyleborini beetles and the phylogeny of Xyleborini beetles of the 28 S r DNA gene are basically consistent.It is possible that the 28 S r DNA gene is more suitable for the phylogenetic analysis of the Xyleborini group.