Chilton N B, Newton L A, Beveridge I, Gasser R B
Department of Veterinary Science, University of Melbourne, 250 Princes Highway, Werribee, Victoria, 3030, Australia.
Mol Phylogenet Evol. 2001 Jun;19(3):367-86. doi: 10.1006/mpev.2001.0938.
The evolutionary relationships of 21 species of trichostrongyloid nematodes were determined by use of sequence data of the second internal transcribed spacer of the ribosomal DNA aligned according to secondary structure information. Irrespective of the method of analysis used, the topologies of the phylogenetic trees derived from the molecular data differed with respect to all four hypotheses proposed previously for the evolutionary relationships of the different subfamilies within the Trichostrongylidae based on morphological data. Thus, the molecular data set did not resolve the conflict between the four previous proposals for the subfamilial relationships. Nonetheless, all trees derived from the molecular data showed strong support for the exclusion of the genera Filarinema and Amidostomum from the clade containing the species within the family Trichostrongylidae. This represents a major difference from the most recent proposal of the systematics of the Trichostrongyloidea in which these two genera were included within the Trichostrongylidae. Therefore, the molecular data support an earlier systematic framework in which Filarinema and Amidostomum were considered to be sister groups of the Trichostrongyloidea.
利用核糖体DNA第二内部转录间隔区的序列数据，根据二级结构信息进行比对，确定了21种毛圆线虫的进化关系。无论采用何种分析方法，基于分子数据得出的系统发育树的拓扑结构，与之前基于形态学数据提出的关于毛圆科不同亚科进化关系的所有四种假说均存在差异。因此，分子数据集未能解决之前关于亚科关系的四种提议之间的冲突。尽管如此，所有基于分子数据得出的树都有力支持将丝虫属和裂口线虫属排除在包含毛圆科物种的进化枝之外。这与毛圆线虫最新的分类学提议存在重大差异，在该提议中这两个属被归入毛圆科。因此，分子数据支持一个更早的系统框架，在该框架中丝虫属和裂口线虫属被认为是毛圆线虫的姐妹类群。
