The Phylogenetic Analysis Of Chinese Theridiid Spiders(Araneae:Theridiidae) With Bell-shaped Retreat Based Morphological And Molecular Data

This dissertation deals with the phylogenetic analysis of Chinese cobweb spiders(Araneae)based morphological and molecular data,which build bell-shaped retreat.Our research contains three main parts: 1.Morphological taxonomy,we provide clear photos,descriptions and distribution data for every species;2.We extract 242 morphological characters for every species accroding to literatures of Theridiidae and form morphological character matrix database;we extrace five gene fragments,including two mitochondrial genes:COI and RNA16 S,and three nuclear genes: RNAs 18 S,RNAs 28 S and H3.3.We carry out the phylogenetic analysis based the above fresh data and the downloaded data from genbank for Theridiidae,with paying more atteention to the group who build bell-shaped retreat.The results show: 1.We collect 6 species of cobweb spiders with building bell-shaped retreat,including 2 new species: Campanicola biuncialis sp.nov.,Campanicola anguilliformis sp.nov.and 4 known species: Campanicola campanulata Yoshida,2015,Campanicola ferrumequina(B(?)senberg & Strand,1906),Cryptachaea riparia(Blackwall,1834),Parasteatoda ducta(Zhu,1998),the male of Parasteatoda ducta(Zhu,1998)is reported for the first time.2.The phylogeny supports some of the major findings of prior studies,the monophyly of Theridiidae and six of seven subfamilies,it also supports the cobweb spiders with bell-shaped retreat to be a monophyletic group.Therefore,we tranfer Cryptachaea riparia(Blackwall,1834)and Parasteatoda ducta(Zhu,1998)to the genus Campanicola Yoshida,2015.3.The phylogeny shows that the species with bell-shaped retreat are located at the top of the tree,which indicates this group newly derived species in Theridiidae.The bell-shaped retreat is thought as the most defensive retreat of Theridiidae according to its structure and materials,therefore,we guess the retreats of cobweb spiders evolve from the simple to complicate.The results of this study not only provide important supplementary materials for the phylogeny and evolution of Theridiidae,but also shed a light for the study of web evolution of Theridiidae.This paper has three parts.First part is literature review,including research history and bridf introduction of Theridiidae.Second part is material and method,including the method and process of the experiment.Third part is result and discussion,including morphological taxonomic results,phylogenetic analysis results,and related discussions.