And Locust Belong To Several Male Reproductive Structure Related To Morphological Differentiation And Classification Research Value

The genus Sinopodisma Chang (Orthoptera:Catantopidae:Podisminae) was erected in1940. Up to now,39species were reported world-wide. The shape of cercus show significant difference in short-wing grasshoppers.They are distributed in southern China, southern Japan and Taiwan. The male supra-anal plate, cercus and epiphallus are important parts of mating organ of Sinopodisma spp.. But the characters of male supra-anal plate, cercus and epiphallus are not used in the classification of this genus.To analyse the supra-anal plate, cercus and epiphallus variation and taxonomic value of Sinopodisma spp.,224male specimens of18Sinopodisma species (13species in the southern China,3species in the Taiwan,2species in the southern Japan) are selected for geometric morphometric analysis. We collected the best combination of13homologous landmarks on male supra-anal plate, the first and5th landmarks as baseline. We collected the best combination of13homologous landmarks on cercus the4th and5th landmarks as baseline. We collected the best combination of14homologous landmarks on cercus, the first and8th landmarks as baseline.We do some different analysis of three characters landmark coordinates, including ANOVA, Correlation analysis, CVA and cluster analysis. The results showed that:1. Size variation of male supra-anal plate, cercus and epiphallus:The ANOVA performed to homogeneity test revealed that the male supra-anal plate, cercus and epiphallus significantly no obvious shape differences between intraspecies. Hotelling’s pair-wise comparisons (post-hoc) showed highly signifcant differences between all species at a low signifcance level (p<0.05). Box plot results show the supra-anal plate, cercus and epiphallus of China Mainland group is smaller than that of Taiwan and Japan groups.2. Correlation ship of size variation among male supra-anal plate, cercus and epiphallus:Correlation analysis of results are moderate positive(0.5<r<0.8) between supra-anal plate and cercus (r=0.656), between supra-anal plate and epiphallus (r=0.739), between cercus and epiphallus (r=0.555). Speculated that among supra-anal plate, cercus and epiphallus meet correlated evolution.3. Shape variation of male supra-anal plate, cercus and epiphallus:Differences between populations were well illustrated by a CVA plot. Each species has its own distribution center, and a certain degree of overlap between species, but on the whole not completely overlap. Anal plate and cercus scatter plots results show can clearly distinguish18species. Epiphallus plots scatter results show that all species, although the overlap is serious, still be able to distinguish species. Relative warp ordination plot results show that main differences focus on end and base of supra-anal plate. Main differences focus on base, upper and lower branch of cercus. Main differences focus on bridge and lateral plate of epiphallus.4. Three characters shape variation regulation:The resultes supra-anal plate of cluster analysis displayed Mainland group showed its closer relation to Taiwan Group.Taiwan Group showed its closer relation to Japan Group. Mainland group showed its more distant relation to Japan Group.The resultes of cluster analysis displayed separate branches. Speculated that Sinopodisma meet gradual model of speciation. Cercus and epiphallus clustering results show that Mainland group, Taiwan Group and Japanese group did not clearly separated. They are indicating the relationship of the three groups more closer. The result is different from the traditional morphological classification and cladistics results.5. The supra-anal plate, cercus and of epiphallus Sinopodisma spp. have significantly taxonomic value.