The phylogenetic positions of the conifer genera Amentotaxus, Phyllocladus, and Nageia inferred from 18s rRNA sequences

Shu Miaw Chaw, Huang Mo Sung, Huei Long, Andrey Zharkikh, Wen Hsiung Lie

研究成果: Article同行評審

44 引文 斯高帕斯(Scopus)

摘要

To determine the evolutionary positions of the conifer genera Amentotaxus, Phyllocladus, and Nageia, we obtained 18S rRNA sequences from 11 new taxa representing the major living orders and families of gymnosperms. With the published Chlamydomonas as an outgroup, phylogenetic analyses of our new data and available sequences indicate that (1) the Gnetales form a monophyletic group, which is an outgroup to the conifers, (2) the conifers are monophyletic, (3) Taxaceae, Cephalotaxaceae, Cupressaceae, and Taxodiaceae form a monophyletic group, (4) Amentotaxus is closer to Torreya than to Cephalotaxus, suggesting that Amentotaxus is better to be classified as a member of Taxaceae, (5) Phyllocladus, Dacrycarpus, Podocarpus, and Nageia form a monophyletic group, and (6) Pinaceae is an outgroup to the other families of conifers. Our finding that Phyllocladus is a sister group of the Podocarpaceae disagrees with the suggestion that the phylloclade of the genus is an ancient structure and that the genus is a terminal taxon within the Podocarpaceae. The genus Nageia is more closely related to Podocarpus than to Dacrycarpus and was derived from within the Podocarpaceae. In conclusion, our data indicate that in conifers, the uniovulate cone occurred independently in Taxacaeae and Cephalotaxaceae, and in Podocarpaceae after the three families separated from Pinaceae, and support the hypothesis that the uniovulate cone is derived from reduction of a multiovulate cone.

原文English
頁(從 - 到)224-230
頁數7
期刊Journal of Molecular Evolution
41
發行號2
DOIs
出版狀態Published - 1995 8月

All Science Journal Classification (ASJC) codes

  • 生態學、進化論、行為學與系統學
  • 分子生物學
  • 遺傳學

指紋

深入研究「The phylogenetic positions of the conifer genera Amentotaxus, Phyllocladus, and Nageia inferred from 18s rRNA sequences」主題。共同形成了獨特的指紋。

引用此