Ecological roles of Xenophyophorean foraminifera in the deep-sea biological communities and early evolution of foraminifera

为阐明异源有孔虫在深海生物群落中的生态学作用和早期有孔虫的演化，本研究进行了分子系统发育分析、超微结构观察和稳定同位素分析。核核糖体RNA分子系统发育分析结果表明，异生体Shinkaiya lindsayi与异生体Syringammina corbicula为姐妹分支，表现为单系关系。我们在鸟岛以东海域进行了为期两天的原位孵化实验。水深5371米。异生菌迅速喂养溶解和颗粒有机物质。虽然在贫营养区，到达深海海底的食物物质有限，但异生菌具有快速生长的潜力，它们表明食物物质的快速吸收。

The purpose of this study is to clarify ecological roles of xenophyophorean foraminifera in the deep-sea biological communities and early evolution of foraminifera, we carried out molecular phylogenetic analyses, ultrastructural observations and stable isotope analyses. The result of molecular phylogenetic analyses of nuclear ribosomal RNA indicates that Shinkaiya lindsayi, xenophyophore, indicates sister clade with other xenophyophore, Syringammina corbicula, shows monophyly relationships. We carried out in situ incubation experiments for two days at east off Torishima Is. at a depth of 5, 371 m. Xenophyophore rapidly fed both dissolved and particulate organic materials. Although limited food materials reached to the deep-sea floor in the oligotrophic region, xenophyophore have a potential for rapid growth, they indicate rapid uptake of food materials.