Shiratori Takashi, Yokoyama Akiko, Ishida Ken-Ichiro
Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Protist. 2014 Dec;165(6):808-24. doi: 10.1016/j.protis.2014.10.003. Epub 2014 Oct 24.
Abollifer is a little-known genus of marine heterotrophic flagellates with no ultrastructural and molecular information, and its taxonomic position remains uncertain. In this study, we report a new species of Abollifer, Abollifer globosa sp. nov., isolated from a seawater sample collected at Tokyo Bay. To reveal the taxonomic position and morphological characteristics of A. globosa, we performed light and electron microscopic observations and a phylogenetic analysis using small subunit ribosomal DNA sequences. A. globosa cells were 29.5 μm in length and 22.4 μm in width, oval or ovoid in shape with an apical projection. Two unequal flagella emerged from a deep subapical flagellar pit. The rim of the flagellar pit except for the ventral side was swollen. Electron microscopic observations showed that A. globosa possessed mitochondria with tubular cristae, a Golgi apparatus, microbodies, extrusomes, and many endosymbiotic bacteria. Basal bodies were arranged in parallel. The flagellar apparatus of A. globosa showed affinity with common gliding cercozoan flagellates. Our phylogenetic tree showed that A. globosa branched as the sister position of order Marimonadida (Imbricatea, Cercozoa). On the basis of the morphological and molecular phylogenetic analysis, we conclude that A. globosa is a new member of the order Marimonadida.
阿博利弗属是一类鲜为人知的海洋异养鞭毛虫，目前尚无超微结构和分子信息，其分类地位仍不确定。在本研究中，我们报告了一种新的阿博利弗属物种，球形阿博利弗（Abollifer globosa sp. nov.），它是从东京湾采集的海水样本中分离出来的。为了揭示球形阿博利弗的分类地位和形态特征，我们进行了光学显微镜和电子显微镜观察，并使用小亚基核糖体DNA序列进行了系统发育分析。球形阿博利弗细胞长29.5μm，宽22.4μm，呈椭圆形或卵形，有一个顶端突起。两条不等长的鞭毛从一个深的亚顶端鞭毛窝中伸出。鞭毛窝的边缘除腹侧外均肿胀。电子显微镜观察表明，球形阿博利弗具有具管状嵴的线粒体、高尔基体、微体、射出体和许多内共生细菌。基体平行排列。球形阿博利弗的鞭毛器与常见的滑行尾丝虫鞭毛虫有亲缘关系。我们的系统发育树显示，球形阿博利弗作为马里莫纳目（Marimonadida，Imbricatea，尾丝虫纲）的姐妹分支。基于形态学和分子系统发育分析，我们得出结论，球形阿博利弗是马里莫纳目的一个新成员。
