关键词: 蝗亚目, 斑腿蝗科, 16S rDNA, 单系性, 系统发生, 分类地位

Abstract:

Fragments of mtDNA 16S rRNA gene were sequenced for 20 individuals from 10 subfamilies of the Catantopidae and 3 individuals of other families of Acridoidea. The homologous sequences of 15 species of grasshoppers were downloaded from the GenBank data library. It was found that the length of the alignment fragments was 397 bp, including 196 variable sites and 157 parsimonious informative sites. In the fragments, the percentages of A+T and C+G were 71.7% and 28.3%, respectively. The numbers of transitions and transversions among pairwise comparisons of the fragments were respectively plotted against percentage sequence difference. The number of transversions was higher than that of transitions, and saturation of transitions was discovered with the increase of sequence difference in the plot. Phylogenies were reconstructed using Tetrix japonica and Teredorus carmichaeli as outgroup with ME, equally weighted MP, weighted MP and Bayesian inference. The monophyly of Catantopidae is not supported by phylogenetic trees. Inside of Cantantopidae, neither Coptacrinae nor Oxyinae is supported as a monophyletic group. The genera Caryanda, Oxya and Pseudonym are closely related. Combining Podisminae and Melanoplinae into one subfamily Podisminae is supported by phylogenetic trees. The current Oxyinae is not a monophyletic group, and should be a polyphyletic group. The result of inferred phylogeny is very different from the classification scheme of Catantopidae based on morphology.

Key words: Caelifera, Catantopidae, 16S rDNA, monophyly, phylogeny, taxonomic status