[Objective] The aim was to explore the phylogenetic relationships among four subspecies of the genus Locusta.[Method] The sequences of three subunits of cytochrome oxidase of Locusta migratoria tibetensis and Locusta migratoria manilensis were amplified and sequenced(COⅠ 1 539 bp,COⅡ 684 bp,CO Ⅲ 792 bp,with the total of 3 015 bp).The corresponding sequenses of Locusta migratoria migratoria and Locusta migratoria migratorioides were obtained from GenBank and constructed a multiple alignment.Phylogenic trees of four subspecies of L.migratoria were constructed by Neighbor-Joining,Maximum-parsimony and Bayesian,respectively.[Result] The average content of A + T in three subunits of four subspecies was 69.57%;the third site of codon showed the highest A + T content,and the COⅠ had the highest A + T content(87.6%);The nucleotide substitution mainly occurred at the third site of codon,and the nucleotide replacement rate of CO Ⅱ was the highest.The second site of codon was conservative,so the replacement rate was in the range of 5.9%-15%.The start codon of COⅠ was CCG or ACG.Genetic distances among four subspecies were ranged from 0.001 to 0.076.The relationship between L.m.tibetensis and Locusta migratoria manilensis was the closest,followed by L.m.migratorioides and L.m.migratorioides,while the genetic distance between L.m.tibetensis and L.m.migratorioides was the largest.[Conclusion] The phylogenetic relationships among four subspecies of Locusta migratoria is L.m.tibetensis,L.m.manilensis,L.m.migratoria,L.m.migratorioides.
The paper reports a new genus of Arcypteridae i e. Suacris gen.nov.and a new species Suacris siyangensis sp.nov.The new genus is similar to Omocestus I Bol ,but differs from the latter in:① Lateral carinae slightly curved,widest 1 6-1 8 times greater than narrowest.② Cubital area wider than or equal to medial area.③Tympanum organ distinct,♂ widely oval,♀ crevice like.The new genus is also similar to Stenobothroides Xu et Zheng,but differs from the later in:①Lateral carinae obvious and curve.②Tergum of terminal abdomere without furcula.③Male subgenital plate long conica.Type specimens are deposited in Northwest Plateau Institute of Biology,the Chinese Academy of Sciences.