Wu Lei, Clamp John C, Yi Zhenzhen, Li Jiqiu, Lin Xiaofeng
Laboratory of Protozoology, Key Laboratory of Ecology and Environment Science in Guangdong Higher Education, South China Normal University, Guangzhou, 510631, China.
Department of Biology, North Carolina Central University, Durham, NC, 27707, United States of America.
PLoS One. 2015 May 6;10(5):e0123720. doi: 10.1371/journal.pone.0123720. eCollection 2015.
Haptorian ciliates in the closely similar genera Kentrophyllum and Epiphyllum possess a unique pattern of ciliature and are distinguished from one another only by the presence or absence of cytoplasmic spines projecting from the margin of the cell. Phylogenetic analyses based on SSU rDNA sequences of three new samples from coastal habitats in China revealed that species in the two genera clustered together indiscriminately (i.e. forms of neither genus clustered into an independent clade) as a maximally supported, monophyletic clade that branches basally to all other clades in the order Pleurostomatida and is strongly divergent from other members of the family in which the genera have been placed. As a result, we propose that Epiphyllum be synonymized with Kentrophyllum and that a new family Kentrophyllidae fam. n. be established for the genus. We hypothesize that the two-sutures of Kentrophyllum is a plesiomorphy within the Pleurostomatida and the unique peripheral kinety might represent an autapomorphy of Kentrophyllum. In addition, we provide a taxonomic revision of Kentrophyllum including description of three new species (K. bispinum sp. n., K. strumosum sp. n., and K. qingdaoense sp. n.), redescription of K. verrucosum (Stokes, 1893) Petz et al., 1995, and three new combinations (K. soliforme (Fauré-Fremiet, 1908) comb. n., K. hohuensis (Wang and Nie, 1933) comb. n. and K. shenzhenense (Pan et al., 2010) comb. n.). The surface ultrastructure of the genus Kentrophyllum is recorded for the first time. And a key to all known species of Kentrophyllum was also suggested.
亲缘关系极为相近的肯氏叶口虫属（Kentrophyllum）和叶口虫属（Epiphyllum）中的触毛目纤毛虫具有独特的纤毛模式，二者的区别仅在于细胞边缘是否有细胞质刺伸出。基于来自中国沿海栖息地的三个新样本的小亚基核糖体DNA（SSU rDNA）序列进行的系统发育分析表明，这两个属的物种毫无差别地聚集在一起（即两个属的形态都没有聚集成一个独立的分支），形成一个得到最大支持的单系分支，该分支在侧口目（Pleurostomatida）中位于所有其他分支的基部，并且与该属所在科的其他成员有很大差异。因此，我们建议将叶口虫属归为肯氏叶口虫属的同义词，并为该属建立一个新科——肯氏叶口虫科（Kentrophyllidae fam. n.）。我们推测，肯氏叶口虫属的两条缝线是侧口目中一种原始特征，而独特的周边动基列可能代表肯氏叶口虫属的一种独征。此外，我们对肯氏叶口虫属进行了分类修订，包括描述三个新物种（双刺肯氏叶口虫（Kentrophyllum bispinum sp. n.）、瘤状肯氏叶口虫（K. strumosum sp. n.）和青岛肯氏叶口虫（K. qingdaoense sp. n.）），重新描述疣状肯氏叶口虫（Kentrophyllum verrucosum (Stokes, 1893) Petz et al., 1995），以及三个新组合（瓶状肯氏叶口虫（Kentrophyllum soliforme (Fauré-Fremiet, 1908) comb. n.）、霍湖肯氏叶口虫（K. hohuensis (Wang and Nie, 1933) comb. n.）和深圳肯氏叶口虫（K. shenzhenense (Pan et al., 2010) comb. n.））。首次记录了肯氏叶口虫属的表面超微结构。还给出了所有已知肯氏叶口虫属物种的检索表。
