| Heteroptera is a large group in insect with a world wide distribution. The main contents of this dissertation include three sections:1) selection and application of the proper DNA barcoding markers in Heteroptera; 2) the phylogeographic studies of some taxa in Heteroptera; 3) the molecular phylogenetic analysis of the Anthocoridae (sensu stricto).The main difficulty of DNA barcoding is to find an ideal gene that discriminates any species in the animal kingdom. The previous studies indicated that COI alone would simply not be sufficent to identify problematic taxa in Heteroptera. In many cases, when a single gene region did not assure complete taxonomic resolution, it could still be resolved fully with additional genetic or other data. When considering complementary barcoding markers, the combination of factors of geographic variation and closely related species needs to be taken into account. We approached this issue by studying four species of the genus Physopelta Amyot & Serville,1843 in first section:Ph. cincticollis Stal,1863, Ph. gutta (Burmeister,1834), Ph. guadriguttata Bergroth,1894, Ph. robusta Stal,1863 and Ph. slanbuschii (Fabricius, 1787). We used the sequence of CO, Cyt b and 16S rDNA from dozen provinces of China and multiplicate algorithms to analyze the intra- and interspecific relationships between these closely related species in the same genus, the results indicate that both COI and Cyt b are the proper molecular markers for DNA barcoding of Heteroptera..The DNA barcoding technique can improve the identification of species and to critically examine the precision of morphological traits commonly used in taxonomy. In the first sention, the sequences of COI gene fragments (1338 bp) of 4 species in the genus Plinachtus Stal,1859 (Heteroptera:Coreidae) from China,Pl.dissimilis Hsiao, 1964, Pl. bicoloripes Scott,1874, Pl. acicularis (Fabricius,1803) and Pl. basalis (Westwood,1842) were amplified. Both the results of the genetic distances of inter-and intraspecies, and phylogenetic analysis based on the COI gene sequences by the methods of NJ, MP and Bayesian, support that Pl. dissimilis and Pl. bicoloripes are same species.Up to now, there are no phylogeographical studies of Heteroptera in China and related area. The results of the phylogeographic reanalysis of the southern green stink bug Nezara viridula (Linnaeus) (Heteroptera:Pentatomidae) in the world by adding the data from China and Iran shows that the acute rising events in the Qinghai-Tibet plateau in the Pliocene-Pleistocene epoch which may have formed the barriers observed separation of the eastern and western Asia clades. The results also support that the basal splitting of African and non-African subgroup was caused by vicariance events related to the collision of the African microplates Apulia and Arabia with Eurasia, and the resultant arise of successive dispersal barriers (e.g. the Red Sea, the Zagros Mountains). The result of the collision of the Arabian Plate with Eurasia during the Miocene probably isolated the African and Eurasian populations. The combined approachs based on phylogenetic analyses, ancestor distritubtions, estimation of node dates, and dispersal-vicariance analyses indicated that the phylogeographical structuring of Anthocoris nemorum group (Heteroptera: Anthocoridae) has been primarily shaped by the two main periods of the Qinghai-Tibet plateau uplift. The DIVA optimal reconstructions suggest that the A. nemorum group diversified from the Miocene to the Pleistocene from a center of origin in the Hengduan Mountains. The rapid uplift of Mountain ranges associated with the uplift of the entire Qinghai-Tibet plateau may have promoted rapid divergence in the A. nemorum group. Vicariance and dispersal were both essential in shaping the present distribution patterns of the A. nemorum group.The third section deals with the molecular phylogenetic analysis of the Anthocoridae (sensu stricto). The family Anthocoridae (sensu stricto) is known as an important group of predators for pests, some of them have been introduced as biological control agents. The previous studies on the phylogenetic relationships within Anthocoridae were based on morphological characters without molecular support. In this study, the molecular markers of 16S rDNA,18S rDNA and cytochrome oxidase subunit I (COI) gene with a total length about 4 kb were employed to analyze the phylogenetic relationships of Anthocoridae (sensu stricto). The phylogenetic trees analyzed by two algorithms (ML and Bayesian) showed that Anthocoridae could be divided into two main lineages. Lineage I contains Anthocorini (except Elatophilus), Oriini, Dufouriellini (only Amphiareus) and Scolopini (only Calliodis). Almeidini, Anthocorini (only Elatophilus), Dufouriellini (except Amphiareus), Xylocorini, Scolopini (only Scoloposcelis) and Blaptusterini were included in lineage II. However, the genus Bilia does not in the same clade with other genera of Oriini, Dufouriellu forms a single calde, and without the close relateiongship with another clade formed by the genera of Cardiastethus, Dysepicritus and Physopleurella. The results indicated that Anthocorini, Dufouriellini, Oriini and Scolopini are paraphyletic groups. We need to establish new tribes to include the genera of Elatophilus and Bilia respectively. Dufouriellini should be divided into three tribes to include Dufouriellus, ((Dysepicritus+Cardiastethus)+ Physopleurella) and Amphhiareus respectively. Two sbutribes of Scolopini:Scolopina and Calliodina should be rised to tribe level.
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