Detailed morphological documentation is provided for established Proschkinia taxa, including the generitype, P. bulnheimii, and P. complanata, P. complanatula, P. complanatoides and P. hyalosirella, and six new species. All established taxa are characterized from original material from historical collections. The new species described in this paper (P. luticola, P. staurospeciosa, P. impar, P. modesta, P. fistulispectabilis, and P. rosowskii) were isolated from the Western Pacific (Yellow Sea coast of Korea) and the Atlantic (Scottish and Texas coasts). Thorough documentation of the frustule, valve and protoplast architecture revealed the combination of characters diagnostic of the genus Proschkinia: a single‐lobed chloroplast; a broad girdle composed of U‐shaped, perforated bands; the position of the conopeate raphe‐sternum relative to the external and internal valve surface; and the presence of an occluded process through the valve, termed the “fistula”. Seven strains of Proschkinia were grown in culture and five of these were sequenced for nuclear ribosomal SSU and plastid‐encoded rbcL. Phylogenetic analysis recovered a clade of Proschkinia with Fistulifera, another fistula‐bearing diatom genus, and together these were sister to a clade formed of the Stauroneidaceae; in turn, all of these were sister to a clade composed of Parlibellus and two monoraphid genera Astartiella and Schizostauron. Despite morphological similarities between Proschkinia and the Naviculaceae, these two taxa are distant in our analysis. We document the variation in the morphology of Proschkinia, including significant variability in the fistula, suggesting that fistula ultrastructure might be one of the key features for species identification within the genus.

中文翻译：

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Proschkinia（Bacillariophyta）的分类学和多样性，来自海洋海岸的一个常见但神秘的属。

详细的形态学文档提供了一种用于建立Proschkinia类群，包括generitype，P。bulnheimii，和P。complanata，P。complanatula，P。complanatoides和P。透明质酸杆菌和6个新物种。所有已建立的分类单元均以历史收藏中的原始材料为特征。新的物种在本文中描述（P。luticola，P。staurospeciosa，P。IMPAR，P。Modesta的，P。fistulispectabilis，和P。rosowskii）隔离于西太平洋（韩国的黄海海岸）和大西洋（苏格兰和德克萨斯州的海岸）。完整的关于壳，瓣和原生质体结构的文献揭示了诊断Proschkinia属的特征的组合：单叶叶绿体。由U形穿孔带组成的宽腰带; 圆锥形胸骨相对于内外瓣膜表面的位置; 以及通过瓣膜的阻塞过程（称为“瘘管”）的存在。七种Proschkinia菌株进行了系统培养，并用其中的五个对核糖体SSU和质体编码的rbc L进行了测序。系统发育分析回收了带有瘘管的硅藻属Fistulifera的Proschkinia进化枝，它们共同组成了Stauroneidaceae的进化枝; 反过来，所有这些都是由Parlibellus和两个单足类Astartiella和Schizostauron组成的进化枝的姐妹。尽管Proschkinia和Naviculaceae之间在形态上相似，但在我们的分析中这两个类群却相距遥远。我们记录了Proschkinia的形态变化， 包括瘘管的明显变异性，表明瘘管的超微结构可能是该属内物种鉴定的关键特征之一。