However , both the monophyly of living amphibians and the close phylogenetic relationships of frogs with salamanders are still debated 然而，现生的两栖类单系起源和蛙类与蝾螈类紧密的系统发生关系一直存在争议。
2.
The complete nucleotide sequence of the mitochondrial genome of f . limnocharis was detailedly compared with those of 5 other amphibians . the nucleotide sequences of 22 trna encoded by 6 amphibians mitochondrial genomes were combined and aligned to the homologous sequences of the 11 veterbrate taxa . using teleosts as outgroup , the phylogenetic analyses results show that mp , nj and ml trees all strongly support the monophyly of living amphibians with respect to other living tetrapods and favor a sister group relationship for caecilians and salamanders 我们在测定了泽蛙线粒体全基因组序列的基础上，与已知其它的5种两栖类进行详细的比较分析，同时选择了11种高等脊椎动物的线粒体全基因序列，以硬骨鱼类做外群，用22个trna基因合并数据进行系统发生重建分析，结果表明mp 、 nj和ml树都强力地支持现生两栖类动物为单系群并且蝾螈类和蚓螈类为姐妹群关系(自引导值分别为92 、 99 、 100 ) 。
3.
The results show that ( 1 ) loops are in general more variable than stems , and in loops a strong adenine bias are observed : ( 2 ) there does not exist a saturation effect in stems , loops or all positions of the 16s rrna gene fragments : ( 3 ) in the molecular cladogram , bagarius forms a sister group with glyptothorax , and euchiloganis forms a sister group with pareuchiloglanis , and exostoma forms a sister group with glyptosternum : ( 4 ) the phlogenetic positions of pseudecheneis , exostoma and glyptosternum are not recognized ; the glyptosternoid fishes are not monophyly although they are defined by 13 osteological apomorphies ; the incongruence of cladograms between molecular and morphological sets may be caused by less informative sites of the 550 homologous sites ; ( 5 ) e . davidi and e . kishinouyei could be the same species according to the genetic distances ; p . sinensis and p . anteanalis could be too 结果表明： ( 1 )环区平均变异位点较茎区多，有很强的a偏好性； ( 2 )没有替代饱和现象； ( 3 )分子系统树上?属和纹胸?属构成姐妹群，石爬?属和?属构成姐妹群， ?属和原?属构成姐妹群； ( 4 ) ?属、原?属和褶?属的系统发育位置不定， ? ?鱼类并未形成一个单系类群；可能的原因是所得到的16srrna基因片段信息位点太少； ( 5 )青石爬?和黄石爬?可能是同一物种，中华?和前臀?可能是同一物种。
4.
The cladogram shows that the opatrini of 14genera in china is not a monophyly , mesomorphus is a monophyly , and another monophyly is composed of others 13 genera . and according to the faunal analysis , we can conclude that opatrini in china is mainly distributed in palaearetic region , hi which the number of genera makes up 59 . 1 % ( 13 genera ) of the total , including 50 % ( 11 genera ) in middle asian subreahn , which combined with distribution of this tribe in the world , so it is proposed that the middle asian subrealm can be viewed as the core of distribution . most of genera distributed in limited area , only gonocephalum distributed in extensive area 根据已知种类，对世界和中国范围内土甲种类的区系组成和地理分布特征进行了首次分析，结论为：世界土甲族以西半球最丰富，古北区最多，其次为非洲区；我国土甲的主体成分是古北区种类，共有12属( 54 . 5 ) ，其中11属( 50 )分布于中亚地区，据此认为我国土甲在区系组成上以中亚成分为主；我国除土甲属gonocephalum广泛分布外，绝大多数属均为狭域分布；蒙新区和华南区的特有属较多，说明中国土甲族具有中亚起源和热带起源两种可能；物种数量分布以蒙新区最多，华南区其次，呈现两极分布格局。
