Sequences from the mitochondrial cytochrome b gene （Cyt b） were determined for 25 species from the superfamily Acridoidae and the homologous sequences of 19 species of grasshoppers were downloaded from the GenBank data library. The purpose was to develop a molecular phylogeny of the Acrypteridae, and to interpret the phylogenetic position of the family within the superfamily Acridoidea. Phylogeny was reconstructed by Maximum-parsimony （MP） and Bayesian criteria using Yunnanites coriacea and Tagasta marginella as outgroups. The alignment length of the fragments was 384 bp after excluding ambiguous sites, including 167 parsimony informative sites. In the fragments, the percentages of A ＋ T and G ＋ C were 70.7% and 29.3%, respectively. The monophyly of Arcypteridae is not supported by phylogenetic trees. Within the Arcypteridae, neither Arcypterinae nor Ceracrinae is supported as a monophyletic group. The current genus Chorthippus is not a monophyletic group, and should be a polyphyletic group. The present results are significantly different from the classification scheme of Arcypteridae, which is based on morphology.
The phylogenetic relationships among all taxa within the Acrididae （Orthoptera： Acridoidea） were largely unknown until now. In this study, to further investigations, 24 species of Acrididae from China were used as sample taxa. The sequence constitutions and variations were analyzed and the molecular phylogenetic trees were reconstructed based on the combined sequence data （795bp length in total） of 12S rDNA and 16S rDNA, using the grasshopper Pyrgomorpha conica of Pyrgomorphidae as the outgroup. The results showed that the rates of the two kinds of transitions are obviously much higher than that of the four kinds of Wansversions in these combined 12S＋16S rDNA sequence data. The saturation ofnucleotide substitutions happened in 12S and 16S rDNA sequence data. The molecular phylogenetic trees indicated that Oedipodinae is a monophyletic group and this subfamily is a natural one, but Catantopinae and Acridinae are non-monophyletic. Oedipodnae is a relatively primitive group within the Acrididae, whereas the Oxyinae may have diverged later than Oedipodinae, but earlier than most other species of Acridide.
