The small phytoplankton genus Triparma belongs to the class Bolidophyceae and contains two distinct forms: silicified species and naked flagellated species (formerly Bolidomonas). Recent studies showed that four silicified species/strains (Triparma laevis f. inornata, T. laevis f. longispina, T. strigata, and T. aff. verrucosa) belong to a single clade that is paraphyletic, because it also contains an unclassified flagellated strain, and is sister to a flagellated species, T. eleuthera. In this study, we isolated and characterized two new strains of silicified species to test the phylogenetic unity of silicified bolidophytes. The isolates were identified as T. retinervis strains because they possessed fine areolation on the cell wall. 18S rDNA and rbcL phylogenetic analyses demonstrated that T. retinervis formed a new silicified clade that is sister to the flagellated species T. pacifica. This reveals that there are at least two distinct clades including both silicified and flagellated Triparma species.

中文翻译：

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属于 Triparma (Bolidophyceae, Stramenopiles) 的硅化菌属的新分支

小型浮游植物属 Triparma 属于 Bolidophyceae，包含两种不同的形式：硅化物种和裸鞭毛物种（以前称为 Bolidomonas）。最近的研究表明，四种硅化物种/菌株（Triparma laevis f. inornata、T. laevis f. longispina、T. strigata 和 T. aff. verrucosa）属于并系群的单个进化枝，因为它还包含一个未分类的鞭毛虫应变，并且是有鞭毛的物种 T. eleuthera 的姐妹。在这项研究中，我们分离并表征了两种新的硅化物种菌株，以测试硅化植物的系统发育统一性。这些分离株被鉴定为视网膜 T.retinervis 菌株，因为它们在细胞壁上具有良好的分离度。18S rDNA 和 rbcL 系统发育分析表明 T. retinervis 形成了一个新的硅化进化枝，它是有鞭毛物种 T. pacifica 的姐妹。这表明至少有两个不同的进化枝，包括硅化和有鞭毛的 Triparma 物种。