Studies on the evolution of characters in the cephalochordates, based on molecular trees of many living species over the world

我们对超过一半的样本(全球15种24个种群)的线粒体全基因组进行了分析，得到了许多重要的结果：(1)揭示了表观鱼属的独特性：(2)表观鱼属已被证明是同源的，其分支最深的是表观鱼属(及其隐匿种，见下文)和其余的(包括其同系物和另一已知的Branchiostoma属的种)；(3)在分子信息库中登记的欧洲柳杉Branchiostoma lanceolata的分子数据与我们对赫尔戈兰和那不勒斯同种的分子数据有很大的不同，而与佛罗里达州的B.floridae相似，这种差异是由于对库中数据的错误识别所致。

We have analyzed the whole mitochondrial genomes of far more than the half of the samples gained during the present project (24 populations of 15 species over the world) and got many important results as follows :(1) The uniqueness of Epigonichthys lucayanus has been revealed.(2) Paraphyly of the genus Epigonichthys has been proved, with the deepest branching between E.lucayanus (and its cryptic species, see below) and the remaining (consisting of its congeners and the species of the other recognized genus Branchiostoma) ; thus the Cephalochordata has proved to be divided into the three (instead of the two in the present system) genera.(3) E.lucayanus has been found to contain two species, which are indistinguishable morphologically from each other.(4) Molecular data of the European lancelet, Branchiostoma lanceolatum registered in the data bank of molecular information has been revealed quite different from our analyses of the same species from Helgoland and Napoli, instead similar to that of B.floridae from Florida ; this discrepancy is attributable to mis-identification of the data in the bank.