Taxonomy On The Theridiidae In Guangxi Zhuang Autonomous Region,China (Arachnida:Araneae)

Guangxi Zhuang Autonomous Region(hereinafter referred to as Guangxi),located in southwestern China,is bounded between north latitude 20°54’ to 26°24’ and east longitude 104°28’ to 112°04’.Guangxi,crossed by the Tropic of Cancer,is one of the regions with the richest biodiversity in China due to bordering tropical ocean in the south,the Nanling Mountains in the north,and the Yunnan-Guizhou Plateau in the west with warm climate,abundant rainwater and sufficient sunlight.Here,we investigated the taxonomic classification of spiders of the Family Theridiidae distributed in Guangxi,using the spider specimens deposited in Hunan Normal University,especially those collected from several National Nature Reserves in Guangxi in recent years.In the first part of dissertation,we briefly introduced the research history,morphological characteristics,classification system and research significance of theridiids,and the basic information of four National Nature Reserves in Guangxi.In the second part of dissertation,according to their morphology,we identified,classified and described over 2000 spider specimens of the family Theridiidae collected from Guangxi,and provided information of specimen collection and observation as well as distribution of species.For all the new species,a detailed morphological description,the comparison with the related species and the etymology are also provided.The list of spider species of Theridiidae from Guangxi is provided in Appendix.There are 108 species of 33 genera including 17 new species.These new species are as follows: Coscinida globosa sp.nov.,Episinus piger sp.nov.,Steatoda vittata sp.nov.,Dipoena bifidaoides sp.nov.,Dipoena membranulaoides sp.nov.,Emertonella rostellatra sp.nov.,Phycosoma nonggangensis sp.nov.,Chrysso nigromaculata sp.nov.,Meotipa caudata sp.nov.,Meotipa latafaba sp.nov.,Meotipa rostrata sp.nov.,Platnickina nonggangensis sp.nov.,Theridion albofasciata sp.nov.,Theridion biprocessus sp.nov.,Theridion cyclosisum sp.nov.,Theridion mulunensis sp.nov.,and Theridion xinjiangensisoides sp.nov.At the same time,the male of Phoroncidia crustula Zhu,1998 is reported for the first time.Color photos of the habitus and genital organs of all new species,the male supplementary and part of known species are provided and a total of 63 plates,206 photos and 4 maps are included in the dissertation.In the third part of dissertation,we analyzed the phylogeny of the known genera of Theridiidae distributed in Guangxi based on 6 different molecular markers using BI and ML.The main goals of this part are to test the monophyly of each genus known from Guangxi,and to discuss the current situation of diverse morphological characteristics and multiple origins of Euryopis.Moreover,we also briefly analyzed the differences between topological structure of phylogenetic tree generated here and the current situation of classification within the family Theridiidae.