Morphological Taxonomy And Molecular Phylogeny Of Common Leaf-mining Jewel Beetles In Jiangxi Province

Leaf-mining jewel beetles occur in two subfamilies(Agrilinae and Polycestinae)in the family Buprestidae of Buprestiodea within order Coleoptera.In this paper,biological characteristics of common leaf-mining jewel beetles in Jiangxi province were analyzed,and the diversity of the leaf-mining jewel beetles and their host plants were systematically studied.The phylogenetic relationship between common leaf-mining jewel beetles in Jiangxi province was studied according to different molecular markers.Major results were as follows:The diversity of leaf-mining jewel beetles and their host plants were analyzed.The family Buprestidae beetles contained nearly 15 000 species,belonged to 21 genera,4 tribes(Tracheini,Aphanisticini,Paratrachini,Xyroscelidini)and 2 subfamilies(Agrilinae,Polycestinae).There were 2604 reported jewel beetles with the behavior of mining leaves,mainly in Tracheini and Aphanisticini.However,there was still no discovery or report about 13 genera in China,including world-distributed Brachys and Lius.Most leaf-mining jewel beetles were monophagous or oligophagous species,rarely euryphagous.Host plants of the leaf-mining jewel beetles were as many as 130 genera,59 families.At the family level,host plants were manily found in Leguminosae(15 genera),Rosaceae(11 genera)and Euphorbiaceae(7 genera),and 36 families contain only 1 genus host plants,while the rest families contain less.Host plant spectra of different leaf-mining jewel beetles were quite different: At the tribe level,Tracheini had the widest host ranges while Paratracheini and Xyroscelidini had narrowest ones.Different host plant feeding various leaf-mining jewel beetles: among which Gramineae and Moraceae possess with 4 genera beetles.The feeding habits of adults and larvae were quite different,and the feeding range of adults was usually larger than that of larvae.In addition,most of them fed on economically important crops such as Sugarcane,soya bean,Pueraria lobata,plum,apricot,prunus,primin and rubus.Large economic losses of crops would be caused by the massive feeding of adults and larvae,but some of them may be beneficial to the control of weeds.Based on the classification system of Buprestidae made by Bellamy CL in 2008,existing literature and field data of the leaf-mining jewel beetles were sorted out,and synonyms were rearranged.There were 13 species of leaf-mining jewel beetles in Jiangxi,while Habroloma and Trachys have 6 species and 7 species,respectively.In addition,new distributed records about Habroloma and Trachys have 5 species and 6 species had been supplemented including 3 unnamed species,respectively,in Jiangxi.Immature stages(eggs,larvae,pupae),ecological characteristics,host plants and distribution information were described,systematically.Pupal morphological characteristics of the two genera were compared.Larval characteristics of the reported 7 genera were compared to obtain the keysto identify 12 species of leaf-mining jewel beetles.Three single gene fragments(18S rDNA,28 S rDNA,COI)of the leaf-mining jewel beetles were sequenced and analyzed.Three methods(Neighbor-joining,Maximum likelyhood,Maximum Parsimony)were used to construct four phylogenetic trees based on single gene and concatenated DNA sequences data from the above three genes.The results indicated that,both 18 S sequences and 28 S sequences of jewel beetles had the bias to G and C bases while the COI sequences and concatenated DNA sequences had the bias to A and T bases.According to saturation analysis,base transition and transversion ratio of the single gene sequences and concatenated DNA sequences of jewel beetles showed the Iss<Iss.c(0.2111<Iss<0.3177,0.725<Iss.c<0.808)based at the condition of P=0.000,indicated that the sequences were not saturated,and thus could be used for phylogenetic analyses.Four phylogenetic trees had similar topology and showed that subfamilies Agrilinae was monophyletic,which clearly separated from Chrysochroinae and Polycestinae.In addition,leaf-mining jewel beetles were mainly found in Trachys species and Habroloma species,which clustered as a clade and separated with each other distinctly.In conclusion,the diversity of leaf-mining jewel beetles and the range of their host plants were high,but there are few systematic studies.The morphology of immature stages and the biology of leaf-mining jewel beetles had been supplemented,which could offer theoretical bases for the prevention cure for pests by leaf-mining jewel beetles.Single genes and concatenated DNA sequences data could help to separate and identify closed species,reflect the phylogenetic relationship among jewel beetles and their sister-groups,which could benefit to the future researches of quick identification and the phylogenetic development of the leaf-mining jewel beetles,and the evolution of larval feeding habits about leaf-mining and wood-mining among jewel beetles.