现代放射虫的高阶分类现状及其生态学意义

THE HIGHER LEVEL CLASSIFICATION OF MODERN RADIOLARIANS AND THEIR ECOLOGICAL SIGNIFICANCE

“放射虫(Radiolaria)”这类原生动物在现代海洋和古海洋研究中具有重要的意义,但其高阶单元分类在传统形态学、细胞微结构和分子系统学研究的不断向前推进中历经了几次大的修订:Phaeodaria(稀孔虫)直至2000年后才经细胞超微结构与分子系统学证实不属于Radiolaria(放射虫);Taxopodia(列足虫)最初被认为是Amoeba(变形虫),后因细胞超微结构而归为Heliozoa(太阳虫),终由分子学证据证实属于Radiolaria;Entactinaria(内射虫)与Spumellaria(泡沫虫)并列为目阶的观点现受到分子系统学证据的质疑;Polycystinea(多囊虫类放射虫)常被用作一正式的分类阶元,但分子系统学证实Polycystinea是一个并系类群,其包含的3个目(Spumellaria、Collodaria和Nassellaria)不是起源于同一分支。此外,本文还着重分析了不同高阶单元类群的生态分布特征及环境应用前景,旨在为国内外学者呈现一个清晰的现代放射虫高阶分类最新进展,便于快速准确地了解不同高阶单元的归类现状及其生态学最新动态,促进现代放射虫在海洋生物学和生态学研究及其在古海洋、古水团和古气候重建研究中的应用发展。

The protozoan“Radiolaria”plays an important role in modern oceanographic and pale-oceanographic studies.The higher level classification has undergone several major revisions in the advancement of traditional morphological,cellular microstructure and molecular systematics.It was not until 2000that Phaeodaria was proved not to be radiolarians based on the studies of cell ultrastructure and molecular systematics.Taxopodia was initially thought to be a kind of amoebae,and was later classified as the Actinophrys due to its cell ultrastructure.Finally,it was proved to be an Order of radiolarians by molecular evidence.Currently,the view that Entactinaria is an independent Order divided from Order Spumellaria is questioned by the data of molecular systematics.Polycystinea is often used as a formal taxonomic unit,while molecular study suggests that it is a paraphyletic group which contains three Orders(Spumellaria,Collodaria,and Nassellaria)in different origins.In addition,this paper also analyzed the ecological characteristics and environmental application prospects of the high Order taxa.Our aim is to present a clear higher level classification of modern Radiolaria for domestic and foreign scholars to quickly and accurately understand the classification status of high Order taxa and its latest developments in biological ecology.Besides,this work will significantly increase the applications of modern Radiolaria on the study of biological oceanography,marine ecology and reconstruction of pale-oceanography,paleo-water masses and paleoclimate.