Molecular Phylogeny of Membracoidea (Insecta: Hemiptera): A Test of Alternative Evolutionary Scenarios

膜总科（叶蝉和树蝉）是一个高度多样化和成功的植食性昆虫谱系，包括25000多个已描述的物种。相互矛盾的基于形态学的系统发育关系假说阻碍了人们理解各种独特的生态和行为特征（例如，反共生、亲代关爱、涂油行为）的进化起源，以及这些特征的获得或丧失在群体多样化中可能发挥的作用。本项目将通过添加大量叶蝉和树蝉物种的核糖体（28S）和蛋白质编码（延伸因子l- α）基因序列的特征，提高膜类科类群之间系统发育关系的分辨率。对这些数据的分析将解决一些长期存在的问题，包括：(1)树跳虫的最初分化是否与跳跃能力的丧失和获得无根的隐幼期同时发生，或者这些是保留的祖先特征？(2)树跳虫是在冈瓦纳大陆分裂之前出现的，就像一种基于形态学的系统发育所暗示的那样，还是像化石记录所暗示的那样，这个谱系是在南美洲大陆分离之后出现的？(3)生境、寄主和/或摄食策略的改变是否促进了某些叶蝉和树蝉种群的多样化？(4)蚂蚁的互惠行为和守卵行为是在几个不同谱系中独立获得的吗？

9726282 Dietrich Molecular Phylogeny of Membracoidea (Insecta: Hemiptera): A Test of Alternative Evolutionary Scenarios Comprising over 25,000 described species, the Membracoidea (leafhoppers and treehoppers) are a highly diverse and successful lineage of plant-feeding insects. Conflicting morphology-based hypotheses of phylogenetic relationship have hindered attempts to understand the evolutionary origins of various unique ecological and behavioral characteristics (e.g., ant-mutualism, parental care, anointing behavior) and the possible roles that the acquisition or loss of such traits played in the diversification of the group. This project will provide increased resolution of the phylogenetic relationships among membracoid family-group taxa by adding characters from nuclear ribosomal (28S) and protein-coding (elongation factor l-alpha) gene sequences for a large sample of leafhopper and treehopper species. Analyses of these data will address a number of long-standing questions, including: (1) Did the initial divergence of treehoppers coincide with the loss ofjumping ability and acquisition of a sessile, cryptic juvenile stage, or are these retained ancestral characteristicsT; (2) Did treehoppers arise prior to the break-up of Gondwana, as implied by one morphology-based phylogeny, or did this lineage arise in South America after the isolation of that continent, as implied by the fossil record?; (3) Did shifts in habitat, host, and/or feeding stragegy promote the diversification of certain leafhopper and treehopper groups?; and (4) Were ant mutualism and egg-guarding behavior acquired independently in several different lineages?