Bhattacharya D, Helmchen T, Melkonian M
Universität zu Köln, Botanisches Institut, Germany.
J Eukaryot Microbiol. 1995 Jan-Feb;42(1):65-9. doi: 10.1111/j.1550-7408.1995.tb01541.x.
The Rhizopoda comprise a diverse assemblage of protists which depend on lobose or filose pseudopodia for locomotion. The biochemical and morphological diversity of rhizopods has led to an uncertain taxonomy. Ribosomal RNA sequence comparisons offer a measure of evolutionary relatedness that is independent of morphology and has been used to demonstrate a polyphyletic origin of the Lobosea. We sequenced complete small subunit ribosomal RNA coding regions from the filose amoebae, Euglypha rotunda and Paulinella chromatophora (Euglyphina) to position these taxa in the eukaryote phylogeny. The neighbor-joining analyses show that E. rotunda and P. chromatophora share a monophyletic origin and are not closely related to any lobose amoebae in our analyses. Instead, the Euglyphina form a robust sister group to the Chlorarachniophyta. These results provide further evidence for the polyphyly of the Rhizopoda and support the creation of a new amoeboid lineage which includes the Euglyphina and the chlorarachniophyte algae; taxa with tubular mitochondrial cristae and filose or reticulate pseudopodia.
根足纲包含各种各样的原生生物，它们依靠叶状或丝状伪足进行运动。根足纲生物在生化和形态上的多样性导致了分类学上的不确定性。核糖体RNA序列比较提供了一种衡量进化相关性的方法，这种方法独立于形态学，并且已被用于证明叶足亚纲的多系起源。我们对丝状变形虫圆疣鳞壳虫（Euglypha rotunda）和嗜盐菌（Paulinella chromatophora，属于鳞壳虫目）的完整小亚基核糖体RNA编码区进行了测序，以便将这些分类单元置于真核生物系统发育中。邻接法分析表明，在我们的分析中，圆疣鳞壳虫和嗜盐菌有一个单系起源，并且与任何叶状变形虫都没有密切关系。相反，鳞壳虫目与绿藻虫纲形成了一个强大的姐妹群。这些结果为根足纲的多系性提供了进一步的证据，并支持创建一个新的变形虫谱系，其中包括鳞壳虫目和绿藻虫纲藻类；这些分类单元具有管状线粒体嵴以及丝状或网状伪足。
